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January 21

Floating on air gas

In the aerogel article, it says newer forms of silica aerogel have a density of 1.9 mg/cm³, which, if I have done my math correctly, is 1.9 kg/m³. On the carbon dioxide page, it lists CO₂ as having a density of 1.98 kg/m³ at 298K (25C). Does this mean that solid aerogel would float on carbon dioxide, or have I misstepped somewhere? --Superiority 10:03, 21 January 2006 (UTC)[reply]

Sounds right to me. Your "floating on air" title isn't right, though, since CO₂ is only around 1% of the content of air. StuRat 10:24, 21 January 2006 (UTC)[reply]

Now, how porous are these extremely low-density aerogels? If you immerse them in (for example) carbon dioxide, won't all the pores fill in with CO₂, increasing the net density of your block of aerogel? (Of course, with a large slab this process might take a while—moving a block of aerogel from air to something like argon, the block would float for a while until enough air was replaced by the heavier gas.) TenOfAllTrades(talk) 15:54, 21 January 2006 (UTC)[reply]

The article says that aerogels are extremely good conductive insulators because they don't allow circulation so the pores shouldn't be able fill with CO2 (must consist of sealed cells). Rmhermen 04:28, 22 January 2006 (UTC)[reply]

Yea, I'm picturing closed cells, like Styrofoam. Is that considered an aerogel ? StuRat 06:51, 22 January 2006 (UTC)[reply]

Well, in that case, I presume it would be possible to gain a large enough quantity of it such that, supported only by a layer of carbon dioxide, a human could walk around on it? --Superiority 14:43, 23 January 2006 (UTC)[reply]

CSS - making background images partially transparent

I want to make the background image of a div partially transparent with the opacity: thingy. The problem is that when I apply this to the div, it makes the bloody text transparent, while the background image is as opaque as ever. Is there a way to get around this? Johnleemk | Talk 13:15, 21 January 2006 (UTC)[reply]

Use a PNG image with alpha channel, so it's semi-transparent. This would be even more compatible than the opacity option in CSS, which is out of the current standards. ☢ Ҡieff⌇↯ 03:19, 22 January 2006 (UTC)[reply]

IE doesn't support alpha channel PNGs, and the only way I know to get around this is to *sigh* go back to CSS. Johnleemk | Talk 04:33, 22 January 2006 (UTC)[reply]

Well, I'd just say "Too bad for IE users". Most browsers DO support PNG transparency and will show it up right, but only IE will fail on this. Alternatively, your opacity property won't be supported by most of other browsers, so it's really all IE's fault. But there are IE fixes that make PNG transparency work, not sure if the full 8 bit alpha channel though.

On a side note, if you make it two divs, one for the background and the other one (inside the last) just for the text, and use the opacity + png transparency method on the bg one, it should work in most cases. ☢ Ҡieff⌇↯ 05:54, 22 January 2006 (UTC)[reply]

Physiology

Why does a bag of intravenous 0.9% normal saline have a pH of 5.0?

Is it? Where did you get the information? See pH and Acidity. I can't help if you want to know which ions are involved. - Mgm|^(talk) 20:10, 21 January 2006 (UTC)[reply]

What? The article Normal saline indicates it only contains salt, so it should be neutral. The physiological pH range for blood plasma is about 7.35-7.45. Injecting something with pH 5.0 into the bloodstream is insane. I don't believe that value. --BluePlatypus 20:50, 21 January 2006 (UTC)[reply]

Comment: Salt doesn't necessarily imply a pH value of 7.0. If it's common salt, yes! deeptrivia (talk) 21:00, 21 January 2006 (UTC)[reply]

Read the article. --BluePlatypus 21:22, 21 January 2006 (UTC)[reply]

An aqueous solution with a pH of 5 is only very slightly acidic; ISTR that standing water can reach that value just by absorbing CO2 from the air, though I'm not sure about that. It represents one gram mole of a monobasic acid in 100,000 liters of water. I imagine the bloodstream has buffers that will easily swamp that out, so it's probably not an issue medically (but I'm not a biologist or medical doctor, so this info comes with no warranty). --Trovatore 21:05, 21 January 2006 (UTC)[reply]

"slightly acidic" in chemistry terms, not in physiological terms. Acidosis occurs below pH 7.35 and you think pH 5.0 is safe? Hardly, try doing the math. pH is logarithmic. Assuming no buffers (which is wrong, but still) with 7 liters of blood at pH 7.35, 0.1 liters of pH 5 solution will bring that down to pH 6.7. And then you're dead. --BluePlatypus 21:22, 21 January 2006 (UTC)[reply]

You're missing the point. If your blood reaches a pH of 5, you're in trouble, no doubt. What I'm saying is, the introduction of an unbuffered aqueous solution having that pH into the blood will probably have very little effect on blood pH, because blood is, I assume, buffered. (Using more weasel words than usual because it's not my field and I certainly wouldn't want anyone to rely on these speculations.) --Trovatore 21:27, 21 January 2006 (UTC)[reply]

True, blood has a pH 7.35-7.45. But a bag of intravenous saline has a pH of 5.0, as indicated on the bag itself. One explanation I can suggest is Stewart's physicochemical principle, and that the strong ions (sodium and chloride) cause dissociation of water, increasing the free hydrogen concentration, and thus lowering pH (since pH is the log of the H+ concentration). Injecitng into blood will cause a slight acidosis as the strong ion difference is reduced (due to the equal sodium and chloride concentrations) - but the body will compensate for this. Patients injected with saline do not become acidotic, unless the mechanism is interfered with (i.e. regular saline infusions over days and days).

This is my theory - I have not come across literature to explain this. --80.42.73.89 21:51, 21 January 2006 (UTC)[reply]

But that doesn't seem to fit common sense to me. I could perhaps accept the fact that the blood may be able to buffer the thing. But why not provide a drip at blood pH to begin with? It seems like a completely unnecessary stress on the body, which is the last thing someone with an IV drip needs. --BluePlatypus 23:06, 21 January 2006 (UTC)[reply]

There are more 'physiological' pH solutions, such as Hartmans (6.5), colloids such as gelofusine etc - it depends on the application. Even stored blood becomes acidic! Acid/Base in the body is still very much a work-in-progress, I think medicine/science has yet to understand even a tenth of the subject. To have a solution with a blood, or rather, extracellular pH would be hard to make as all individuals are different, and all the things that give us a 'pH' - ions, carbon dioxide, undetermined acids/bases etc, for all the different clinical situations that are encountered, would be impossible.

Actually, pH regulation in human beings is understood pretty well. There are no major "unsolved mysteries" or "big questions" remaining. NS has a pH of 5 off the shelf, but is quickly and easily buffered by the human body as it is infused. Blue Platypus was trying to reason it out but was working with several wrong assumptions about volume of diffusion and buffering capacity of blood and body tissues. There are iv solutions designed to mitigate (or not exacerbate) acidosis (such as lactated Ringer's solution), but there are very few clinical situations where you could detect an advantage. Also note that there is a lot of quackery out there about how the body handles acids and acidic foods that is pure nonsense. alteripse 18:19, 22 January 2006 (UTC)[reply]

I still share BP's curiosity, though: Is normal saline actually titrated to a pH of 5? If so, why? Granting that the amount of acid is physiologically irrelevant, still, surely it must have some purpose or it wouldn't be there. --Trovatore 18:41, 22 January 2006 (UTC)[reply]

I don't think it is intentionally titrated to pH of 5. I think that just happens to be what you get when you make up the commercial products (which date to the first half of the 20th century) and no one has ever considered it a significant enough problem to adapt any of the proposed replacements widely. I omitted these speculations from my previous answer because they are speculations, and I may be wrong. I do have a high level of confidence in the reliability of the paragraph above. alteripse 18:55, 22 January 2006 (UTC)[reply]

Problem with SVG format

When I upload Image:deeptrivia.svg, it comes out to be blank. But on Inkscape, it just appears fine. I have tried both plain svg and inkscape svg formats. Even when I redownload the uploaded image and open it on inkscape, it appears fine. The image should look like Image:deeptrivia.png. What is going wrong? deeptrivia (talk) 20:46, 21 January 2006 (UTC)[reply]

Start with the obvious: Does your browser support SVG images? --BluePlatypus 20:53, 21 January 2006 (UTC)[reply]

Sure. It does. Could you see anything on clicking on Image:deeptrivia.svg ? deeptrivia (talk) 20:58, 21 January 2006 (UTC)[reply]

With Firefox 1.0.6, it doesnt show up. Have you considered simply uploading it in a different file format? GeeJo _{(t) (c)} • 21:18, 21 January 2006 (UTC)[reply]

Yeah, Image:deeptrivia.png. But I'd like it to be scalable. deeptrivia (talk) 21:31, 21 January 2006 (UTC)[reply]

I see a white rectangle, which is also what Firefox shows when viewing the SVG file directly, and also what I see when I open the file in Inkscape. Are you sure you uploaded the correct version? —Ilmari Karonen (talk) 21:24, 21 January 2006 (UTC)[reply]

Strange, because I again downloaded the file (saved with a different name of course) and opened it in Inkscape, and it again shows correctly! Could it be because I'm using a font to write in an ancient script, which would not be available on your computer? deeptrivia (talk) 21:30, 21 January 2006 (UTC)[reply]

The problem is almost certainly because you're using a font that Wikipedia's SVG renderer doesn't have, and for which it can't make a reasonable substitution. Note that whether your browser supports SVG is irrelevant; Wikipedia doesn't send your browser an SVG, it rasterises it into a PNG - and in order to rasterise text it has to have either the exact font you specify or a compatible fallback. The offending line in the SVG is "font-family:brahmi lipi rabison", and I think mediawiki doesn't have access to any of those fonts. There is a solution. You can't embed a font in an SVG, but you can convert the characters from a text object into a vector. Do that with path->object_to_path. Note that this means you'll be including the shapes of the glyphs themselves into the file you upload to wikipedia (rather than just a few chars of unicode text and a font name). You can only do that if the font you're using is licenced under a Wikipedia-compatible licence; as a derivative work, the SVG this process will produce will be licenced under that licence too. -- Finlay McWalter | Talk 21:56, 21 January 2006 (UTC)[reply]

Thanks a ton! That worked. I don't know what license the font has, but I downloaded it for free from the internet. deeptrivia (talk) 22:09, 21 January 2006 (UTC)[reply]

Then you must assume it's not safe to use. —Keenan Pepper 22:17, 21 January 2006 (UTC)[reply]

I've emailed the creator of the font regarding the matter. deeptrivia (talk) 22:38, 21 January 2006 (UTC)[reply]

Sourceforge has a GPL Brahmi font at [1]. Whether GPL and GFDL are compatible licences is a matter above my paygrade. -- Finlay McWalter | Talk 22:42, 21 January 2006 (UTC)[reply]

Incidentally you image looks bad on a non-white background. That's because there's a big white rectangle stuck to it, near the bottom. Ungroup, delete the white rectangle, and save. It looks like you were trying to have a white background, but really that's not necessary, and Mediawiki's SVG renderer will correctly render the transparent SVG background to a transparent area of the resulting PNG. -- Finlay McWalter | Talk 22:48, 21 January 2006 (UTC)[reply]

Thanks, I made that change. It seems the sourceforge fonts are for modern scripts based on the Brahmi script. deeptrivia (talk) 22:56, 21 January 2006 (UTC)[reply]

most enzymes are...

are most enzymes lipids, phospholipids, proteins, or carbohydrates?

Look at the first ~~sentence~~ five words of Enzyme. —Keenan Pepper 22:14, 21 January 2006 (UTC)[reply]

oh, sorry, i must have missed that, thanks. --Herzog 22:16, 21 January 2006 (UTC)[reply]

Interesting question. What I'd want to know is if most enzymes are proteins, which ones aren't? :) --BluePlatypus 23:01, 21 January 2006 (UTC)[reply]

All enzymes are proteins by definition. There are non-protein catalysts, though, including some RNAs and metals (e.g. platinum). --David Iberri (talk) 23:14, 21 January 2006 (UTC)[reply]

It was a rhetorical question. --BluePlatypus 23:21, 21 January 2006 (UTC)[reply]

Really? I completely missed that. In any case, maybe someone will find the info useful. --David Iberri (talk) 17:24, 22 January 2006 (UTC)[reply]

Danger in dissembling electronic devices?

I enjoy dissembling certain types of electronics, both just to see what the insides look like, and to try to learn more about how they work. I notice that on many devices it says something to the effect of "danger risk of electric shock if opened". I haven't been electrocuted by any of them yet, but I'm wondering if there is really any danger. If there is, how can I tell which parts(including wires) are safe to touch/disconnect and which ones aren't? Flea110 22:58, 21 January 2006 (UTC)[reply]

Capacitors store electric charge, and they are dangerous to touch, as well as anything connected to them. I've got to say though: If you need to ask, then you probably shouldn't be doing it. Perhaps you should start with some simple home-electronics kits and books before you start cracking open unknown electronic devices. Once you open that thing there is nothing in there that indicates 'this part is dangerous'. Not only that, but parts which are supposed to be safe may not be. (I've gotten shocks from things that should have been grounded) So even knowledge isn't a catch-all. And whatever you do, don't open a TV, monitor or other form of CRT. Those things have enough juice stored in them when they're off to kill you. --BluePlatypus 23:15, 21 January 2006 (UTC)[reply]

And especially don't open a defibrillator! hydnjo talk 23:20, 21 January 2006 (UTC)[reply]

What sort of "simple home-electronics kits and books" do you mean? Can you give me some examples? Flea110 23:33, 21 January 2006 (UTC)[reply]

This magazine website should give some indication of what hobby electronics constructors get up to. --Robert Merkel 00:29, 22 January 2006 (UTC)[reply]

Well there are all kinds of beginners and hobbyist books and magazines on electronics (See above, or just check your local bookstore, or an online one). As for kits, I've heard good things about Ramsey. They've got electronics kits for all kinds of stuff, including beginner ones which teach the basics. There are others too, just look in some hobbyist magazines or catalogs, or search online. --BluePlatypus 01:14, 22 January 2006 (UTC)[reply]

Dissembling electronic devices can be very dangerous. Some people think they swung the election to Bush in Ohio. Or they can just be annoying. Take my bathroom scale, the lying son of an adding machine.... --Trovatore 01:25, 22 January 2006 (UTC)[reply]

It might be obvious to most, but just in case...

Always unplug any electronic device and remove any batteries before working on it.

Let it sit for a long time to ensure most capacitors will have discharged. StuRat 06:37, 22 January 2006 (UTC)[reply]

Also, keep in mind that disassembling things tends to void warranties. Remember the difference between a geek and a normal person is thus: when the warranty expires, a normal person says, "Ah, it's going to break now," whereas a geek says, "Sweet, I can take it apart!" Cernen Xanthine Katrena 07:05, 24 January 2006 (UTC)[reply]

January 22

Attention Deficit Disorder?

I am a sophmore in college. I can't remember when the last time was that I concentrated on school work, while completely sober, for more than two hours at once. Most of my major papers and tests are handled with the aid of amphetamines (which I only use approximately once a month). However, I can concentrate on things that I am enjoying for extended periods of time. For example, I did exceptionally well in high school debate and I can read a good book for a few hours. Is there a chance that I have ADD? What can I do that might help me to concentrate on school work? Thanks for the help!

See a doctor. We unfortunately are not in a position to provide diagnoses. enochlau (talk) 00:36, 22 January 2006 (UTC)[reply]

Actually a psychiatrist would be better for that kind of diagnosis. But you can check out the article on ADHD, or see the ASRS symptom checklist. (Note that the checklist results do not constitute a diagnosis.) But from what you've said here, I don't think it sounds like you've got it, though. In my experience ADHD is far more extreme, where you'd either be unable to concentrate for more than ten minutes, or you'd be 'hyperconcentrating' and completely lost for hours on end. Not being able to concentrate on things you find boring is normal, what really defines ADHD (in my subjective, non-expert opinion) is that those with it cannot concentrate on the things they do find interesting. --BluePlatypus 00:55, 22 January 2006 (UTC)[reply]

In the United States at least, a psychiatrist is a doctor, although the converse of course is not necessarily true. — Knowledge Seeker দ 01:26, 22 January 2006 (UTC)[reply]

Two hours isn't bad at all. Just take a break every two hours, then get back into it. If that doesn't work, try spreading the studying and work over several days, and alternate subects to keep from getting bored to death. StuRat 06:20, 22 January 2006 (UTC)[reply]

Coming from someone who has ADHD himself, I can tell you that ADHD is comparable to not being able to focus and at the same time being excited about everything. ADD is a little more like apathy, only you do care, but not enough not to change subjects every six seconds. ^_^ Cernen Xanthine Katrena 08:10, 22 January 2006 (UTC)[reply]

Need Help Identifying Plants

I'm no botanist, just a photographer. I request help in identifying the four pictures I have uploaded to the commons, which can be found on my Photography Page. Please feel free to label, categorize, or use any of these images if you can help me. Thanks in advanced. M@$+@ Ju ~ ♠ 01:10, 22 January 2006 (UTC)[reply]

lasers

Hello, Would you tell me what type of portable laser could be used to cut through ice but not harm people and not be effected by metal. I'm looking for type and power level. I suppose solid state and a moderate power level would work. I'm picturing like a saw with the beam going between 2 points andcutting the ice as it moves through it. Thanks. Scott

I would be afraid that ice would reflect or refract enough laser light to cause eye damage. StuRat 06:16, 22 January 2006 (UTC)[reply]

Seems a tricky and exceedingly complex and expensive way to cut through ice. You'd probably get excellent results with a thin wire extended between two points. Just get this wire constantly hot and it'll do the job very well. My best idea would be getting a wire of a material with great electrical resistance and letting a current go through it, but if you're willing to try that, you'd better be extremely cautious to not cause a short circuit, not get yourself electrocuted and just really understand that electricity can kill you. :P ☢ Ҡieff⌇↯ 03:25, 22 January 2006 (UTC)[reply]

Too uneconomical, sorry we can't help you write your science fiction novel :( --

Mac Davis ☢ ญƛ. 09:49, 22 January 2006 (UTC)[reply]

Well, as others have pointed out it seems to be a heck of an inefficient way of cutting ice, but to answer your question, you'd need a laser categorised as a class IV ("typically more than 500 mW if cw, or 10 J/cm2 if pulsed") under the categorisation system. You can find the description in the laser safety article. --Noodhoog 20:34, 22 January 2006 (UTC)[reply]

Tail Spin - More information?

Not sure if I have the terminology correct--tail spin--but where can I find more information about it? My understanding is that when a jet-based aircraft stays at the same horizontal position and spins about the vertical axis towards the ground, it's referred to as a tail spin. Last I heard, there was no direct known cause, and there were mysteries surrounding recovery from such a situation. Where can I find more information about it? --24.231.16.6 03:15, 22 January 2006 (UTC)[reply]

Well, you can start with spin (flight). --Anon, 03:45, January 22.

Very cool; thanks, I just got my terminology mixed up. --24.231.16.6 05:49, 22 January 2006 (UTC)[reply]

The term is also used for any "steady downward spiral", such as the collapse of Enron. StuRat 06:09, 22 January 2006 (UTC)[reply]

Another cute name that is related is 'Death Spiral' [2] --Zeizmic 13:10, 22 January 2006 (UTC)[reply]

Web Page Color

This page's background color is blue in Internet Explorer but black in Firefox. Why? Gerard Foley 04:30, 22 January 2006 (UTC)[reply]

Actually, while people are there, any comments (good or bad) about the design of the page and how to improve it? Thanks, Gerard Foley 04:39, 22 January 2006 (UTC)[reply]

Near the top of the HTML code you have: bgcolor= "pics/sky blue bg". You should use just the number code or the name (bgcolor="blue") of the color you want. --jh51681 05:35, 22 January 2006 (UTC)[reply]

I saw that line, but how does it work? Gerard Foley 05:40, 22 January 2006 (UTC)[reply]

Don't use bgcolor, use style="background: blue url(path/filename.ext)" ☢ Ҡieff⌇↯ 05:45, 22 January 2006 (UTC)[reply]

I just don't understand what bgcolor= "pics/sky blue bg" does. Gerard Foley 06:32, 22 January 2006 (UTC)[reply]

Nothing, AFAIK, since that's incorrect code. Correct code would be bgcolor="blue" or bgcolor="#0000FF". "pics/sky" is not a valid "color", so browsers will respond to it differently. ☢ Ҡieff⌇↯ 09:04, 22 January 2006 (UTC)[reply]

But that still doesn't explain why some browsers make the background blue, such as Konqueror (Mozilla makes it black). http://www.thebiosoundmethod.com/pics/sky blue bg doesn't exist (tried various punctuations too). Do they pick up the 'blue' bit and ignore the rest? DirkvdM 10:02, 22 January 2006 (UTC)[reply]

It's rather simple:

Konqueror gets the bgcolor argument as a series of words "pics/sky" "blue" and "bg". It goes through them until it finds a valid argument. In this case, this would be "blue".
Firefox gets only the first word, since the HTML standard says bgcolor only has one parameter. Since "pics/sky" is not a color, it think it has to fill the value in with some standard base color, which in this case is black.
Other browser may treat "pics/sky" as an actual color argument and depending of the algorithm, they'd present different colors.
And at last, some browsers will just ignore it as invalid and use the default background color. ☢ Ҡieff⌇↯ 22:39, 22 January 2006 (UTC)[reply]

Thanks, Ҡieff. Gerard Foley 03:19, 23 January 2006 (UTC)[reply]

As crude as the site is, I actually kind of like it, and like the navigation at the bottom of the page. Where it says "Biosound method way to reduce stress" and that paragraph, you should make the font size a bit smaller. — Preceding unsigned comment added by Mac Davis (talk • contribs)

<shock> You like it!? You're joking right? Gerard Foley 07:45, 22 January 2006 (UTC)[reply]

FWIW, it shows up in blue on Safari as well. And I don't like the large type. It makes me think that quantity (size of the text) is trying to make up for a lack of quality (what the text actually says). Dismas|^(talk) 14:20, 22 January 2006 (UTC)[reply]

schizosaccharomyces pombe

Hello, I am just an average guy who enjoys home distilling as a hobby. I have done a little research about yeast strains, a little mind you. I was wondering where I could purchase a strain of schizosaccharomyces pombe yeast. If you know of any sites that I could make such a purchase I would be most appreciative. Thank you for your time and effort in advance. Patrick Kelty.

My first Google hit. Avoid the mutant strains if you want to brew. --JWSchmidt 05:32, 22 January 2006 (UTC)[reply]

Refutations of Arguments Against the Multiverse Hypothesis

I am going to give some counter-arguments refuting the arguments many people have made against the theory of Parallel Universes:

First, I've heard that the theory of Parallel Universes isn't very scientific.But just because a particular belief,idea or guess isn't scientific doesn't mean it's not true, or it can't be true.Look at all those religions and religious beliefs in the world.Those beliefs which many of the religions in the world are based on or teach aren't very scientific, but that doesn't mean that they're not true!! I've heard some creationists say that the theory of Parallel Universes can not explain why the Universe has the conditions,physical laws and physical constants needed for life to exist, because there's no evidence to prove it.Actually, things are the other way round.The fact is, there is evidence to prove it is true because it explains very well why the Universes has the fine-tune conditions needed for life exist.After all, people have also said the theory of intelligent design is not true because of that sort of stuff.

There's a name for that theory, but I can't quite say it... "Of course the universe is the way it is, if it was any other way we wouldn't be here to see it". Tzarius

I wouldn't call it a theory, it's quite obvious that if the universe couldn't support life then we wouldn't be here to see it. Therefore, any universe we can observe must be capable of supporting life. I suppose you could call this a biased sample. Since we can only sample universes capable of sustaining life, we get a very biased view of what the typical universe looks like. StuRat 07:06, 22 January 2006 (UTC)[reply]

Just now I found the correct search terms - it's the Anthropic principle. Tzarius 08:22, 22 January 2006 (UTC)[reply]

Second, I've that the Multiverse hypothesis is not true because some scientists say that it's inevitable that the Universe turned out the way it is.Are they saying they know the reason why the Universe is the way it is, with all those physical laws,rules,principles and constants?First, isn't that pretty arrogant?Second, what is reason they know that the Universe is the way it is?If they don't know why the Universe has the laws and physical constants that it has, then they shouldn't make such an arrogant claim!!

Doesn't matter what theory you're talking about. You can argue everything down to the basic "But why?" and the scientific method cannot provide the answer. Tzarius

Also note that religion comes down to unanswereable questions, too. Where did God come from ? Why does he care about us insignificant mortals ? Etc. StuRat 07:00, 22 January 2006 (UTC)[reply]

Third, I've heard that the exist of many universes raises the question of whether virtual worlds generated by conputers and virtual reality should be counted among them.The existence of other universes means the existence of places and areas of space that you cannot reach no matter how far travel across the Universes.So the virtual worlds contains virtual objects, and are generated by computer or VR, are virtual or 'imaginary' Parallel Universes.

Sure. There could well be an infinite number of other universes, unreachable by any means from this one. But since they can't possibly affect this universe, they can be safely ignored. Tzarius

Fourth, I've heard that the Multiverse hypothesis violates Occam's Razor.By making such a theory, you then have to explain why different universes have different physical laws and constants.First, the Multiverse hypothesis is the simplest explanation!Intelligent design is far more complicated.Second, many theories have parts of them which unexplained when they were first made.For example, Newton's theory of gravity didn't explain why gravity exists.And even when the general theory of relativity explained it as a distortion of space time, that didn't explain why matter distorts spacetime.And when Darwin's theory of evoltuion was made, it at first didn't explain why different animals have differentlevels of survival ability in the first place or how living things originated in the first place.Third, as to what other universes might be like, that's very interesting.Who knows?One of them might even be like the world of Narnia in the story, the Chronicles of Narnia. Please tell the people who have been arguing against the multiverse hypothesis about my refutations or counter-arguments!!!!

Any theory must be supported by observation or mathematical calculations and preferably both. Those theories you listed were all supported by observation first. There may be some support for the parallel universe theory as observations of double slit experiments seem to show interference between photons even when only one is launched at the slits at a time. One explanation is that photons from parallel universes are causing the interference. There may also be some support in the math, as one interpretation of the wave probability function is that it predicts the probability that a wave packet will be in a given universe at a given time. StuRat 07:34, 22 January 2006 (UTC)[reply]

By your own admission, the parallel universes theory "isn't very scientific". If it cannot be proven or disproven, then it does not belong in Science, and will remain on the fringes of fancy. Tzarius 06:20, 22 January 2006 (UTC)[reply]

I believe it is a scientific theory, which can be tested and proven or disproven. At present, there is only limited proof to support it, so it should be considered only a possibility. If more evidence supports it in the future, then it may become more of a mainstream theory. StuRat 07:47, 22 January 2006 (UTC)[reply]

As far as I am aware, there is currently no way for us to distinguish between any of the Interpretations of quantum mechanics. Each one avoids some of the problems, but also comes with its own baggage. I remember reading about a proposal for using a variation of the Double-slit experiment to attempt to prove the many worlds interpretation, but I can't find any references at the moment. --GraemeL ^(talk) 14:36, 22 January 2006 (UTC)[reply]

Double-slit experiment#The_thought_experiment does get close when it talks about applying the wave probability function of Quantum Mechanics to individual photons, but it does stop short of suggesting that the photons may simultaneously exist in many linked universes, some of which have it going thru the left slit and some of which have it going thru the right slit. StuRat 09:24, 23 January 2006 (UTC)[reply]

inductor

want 2 know about the properties of the inductor

Perhaps you didn't realize this, but this is actually an encyclopedia where you can answer most questions yourself using the handy search bar along the left side of your screen. Type in "inductor", press "Go", and marvel at the wonder that is modern technology. --David Iberri (talk) 07:04, 22 January 2006 (UTC)[reply]

Fillings

I'm not looking for medical advice here, just someone to blame. (It'll probably end up being me.) What can cause an amalgam filling to crack? I'd love to think it was my dentist doing a sh*tty job, but one can only be so hopeful. Cernen Xanthine Katrena 08:07, 22 January 2006 (UTC)[reply]

[3] Here you go, a bit for you to read. :smile: --

Mac Davis ญƛ. 09:47, 22 January 2006 (UTC)[reply]

Biting on hard candy. Happened to me once (while at a festival abroad - very inconvenient). It was an old filling. But I suppose that your crack (no pun) was not in an old filling (still no pun) and didn't have such an obvious cause, because else you wouldn't have asked. In other words, did it crack 'just like that'? DirkvdM 10:10, 22 January 2006 (UTC)[reply]

You're all getting old. :) --Zeizmic 13:05, 22 January 2006 (UTC)[reply]

Fillings crack for the same reason other things crack: the forces to which they are exposed exceed their compressive or tensile strength. This could indeed be partially the dentist's fault, if he selects a filling material that is inappropriate to the situation. For example, the use of dental amalgam in a setting where a full crown is more suitable might be considered unrealistically optimistic. However, this type of treatment compromise is made all the time, for the sake of economy. And as often is the case, a short-term economy eventually leads to extra expense if the selected material is not sufficiently durable.

Fillings also crack when they either become weakened or are subjected to abnormally high forces. For example:

when you chew on them too soon after being placed, and before they have fully solidified (this can initiate cracks that do not become manifest until sometime later);
as a result of metallurgical work-hardening over years of loyal service;
as a result of an undermining of their support by decay that extends under the fillings;
as a result of sudden, unexpected high-magnitude forces-- such as encountering a pitted prune, date, or olive that wasn't pitted;
as a result of inappropriate of non-functional tooth use, such as habitual tooth clenching/grinding, chewing on ice cubes, etc.

So, either the patient, the doctor, or plain dumb luck may be responsible for structural failure of a filling.--Mark Bornfeld DDS 15:01, 22 January 2006 (UTC)[reply]

Ah! A dentist doth respondeth! Mine own eyes art stunned at thy brevity! Er...I mean...thank you all, you have been extraordinarily helpful. I do tend to eat ice cubes, and it wouldn't surprise me if my dentai insurance wasn't going to cover a crown, so he did an amalgam filling to save me money (of course, it wound up costing me over three hundred dollars anyway...). At least now I know I can blame us both. Thanks again. Cernen Xanthine Katrena 10:57, 23 January 2006 (UTC)[reply]

Windows XP Pro activation

I have the OEM version of Windows XP Pro installed on my current computer which I built myself. But I've just bought some new kit to build a replacement computer (new case, CPU, motherboard , VGA card and SATA hard-drives), because my current set-up is a bit tired. I plan to migrate everything from the old computer to the new one and re-use my existing version of Windows, but during the time of migration I expect that both computers will be in use until I retire the old set-up. I know there's a 45 day period where you don't have to activate Windows, but am I right in saying that I need to activate it in order to download the hotfixes etc? If I try to activate Windows on the new computer will it work or will it fail or will my old computer stop working because it think that I've got a pirated version? MrMcarthy

From what I understand, an OEM version of Windows XP is tied to the computer that it was bought with, which is why they are sold at a discount compared to the retail versions. So, no I don't think it will activate on the new computer. Ignoring that, you should be able to install hotfixes regardless of whether it has been activated or not - the Update service will only lock you out if you have a serial number that's known to be pirated. enochlau (talk) 11:43, 22 January 2006 (UTC)[reply]

If you activate it by calling Microsoft, you should be put through to a human if the activation fails, so you can explain the situation and (hopefully) get the activation code. They were quite reasonable when I went through that with Office XP - although that wasn't an OEM version, so that might make a difference. --Pidgeot (t) (c) (e) 14:32, 22 January 2006 (UTC)[reply]

You generally can't move an OEM copy of Windows to a new machine without breaking the terms of the license. The OEM copy was sold at a discount on the understanding that it goes to landfill with the computer. This is actually one reason why it is almost always cheaper to buy a new machine with Windows loaded than you can make one and install legal software: the OEM license cost the manufacturer much less than you could buy Windows at retail. (Note that sites offering "OEM software" in single copies are almost always selling pirate software). Notinasnaid 19:23, 24 January 2006 (UTC)[reply]

Origin of the brand name "Asus"

Hi, our article about ASUSTeK claims that the "brand name 'ASUS' originated from the word 'Pegasus'", which is something I haven't found any reference for on the web. Could someone point me to a reliable source for this or for the real origin? Thanks --Gennaro Prota 12:31, 22 January 2006 (UTC)[reply]

Well, I found a reference on the web here saying ASUS used to be Pegasus (as in the flying-horse of Greek Mythology) but had to change their name in many countries for Trademark purposes. So they dropped the "Peg".. It's a second-hand account, but it's such a trivial thing that I don't see any reason to doubt it, lest someone from ASUS themselves says something. --BluePlatypus 21:26, 22 January 2006 (UTC)[reply]

Wow, thanks! This renewed my hopes to find something through search engines, so I also tried Yahoo!, Altavista and others :) Finally I came up to this two articles, which I translated with the online Babel Fish service:

If you do so as well you will discover that, yes, the name is said to derive from "Pegasus", however the "official explanation" for dropping "peg" seems to be that they wanted their name to be "high" in alphabetical listings (sic!). Wikipedia, of course, shall only report verifiable information so I think I'll add the two links above to our article (plus the Babel Fish URL). Thanks again, Gennaro Prota 12:59, 23 January 2006 (UTC)[reply]

ability to walk

what is the reason behind our ability to walk??is it friction or newton's third law of motion(every action has an equal and opposite reaction) thank you andrea

This sounds like homework! But surely both of them have a role, since without friction it would be like walking on ice, and without Newton's Third Law, you'd sink into the ground since it wasn't pushing back. And there must be countless other physical laws involved (Hooke's Law on the tendons in your legs, Ohm's Law for the electric current from your brain etc.) smurrayinchester^{(User), (Talk)} 16:29, 22 January 2006 (UTC)[reply]

Ehm, that 'electic current' is really a succession of chemical reactions, I believe, so I'm not sure Ohm would have anything to say on this. The neuron article says it's electric, but from neurotransmitter I understand that both can be true at the same time. DirkvdM 09:27, 23 January 2006 (UTC)[reply]

Douglas Adams once said (I'm pretty sure it was him ... correct me on this?) in a similar arrangement of words: Walking is merely the ability to catch yourself while you fall forward at a consistant rate. So from that you could assume Newton's first and third were most important, although pretty much every law of fundamental physics is involved in some form or another! freshgavin TALK 23:36, 24 January 2006 (UTC)[reply]

Calculating a molecule's electronegativity

Ditto. How do I do that? I didn't find anything useful on the electronegativity page and with a wikipedia search. Whitetigah 15:03, 22 January 2006 (UTC)[reply]

Well for Mulliken electronegativities, it's right there. For Pauling's, see his book The nature of the chemical bond. --BluePlatypus 19:49, 22 January 2006 (UTC)[reply]

For a molecule you probably want an electrostatic potential map which gives you an idea of the charge distribution around the molecule. Potential maps of molecules tend to be dotted around chemistry textbooks and look something like this. These are usually calculated on computers using mathematical models that are developed by theoretical chemists. Accuracy, of course, depends on the model you choose and the computing time you wish to spend on the problem. Is not convenient to calculate these by hand at all, even for the simplest molecules. -- Run e Welsh | ταλκ 22:36, 23 January 2006 (UTC)[reply]

capacitor

should capacitor be used only in ac circuits? if so why do most dc circuits have capacitors? — Preceding unsigned comment added by 61.1.217.105 (talk)

I'm not an expert on the subject, but I see no reason why capacitors should be used in AC circuits but not DC circuits. In fact, capacitors can be used in both types of circuit. Perhaps someone experienced in the topic will stop by soon to give you a better answer; for now, you might read up on the subject at our article on capacitors. --David Iberri (talk) 17:20, 22 January 2006 (UTC)[reply]

Capacitors have functions in both AC and DC circuits. Did you read the Capacitor article? hydnjo talk 18:35, 22 January 2006 (UTC)[reply]

It seems that the questioner feels that capacitors are only used to block DC voltage, allowing AC signals to pass. Capacitors are also used to hold a charge that may be discharged when needed. --Kainaw ^(talk) 00:30, 23 January 2006 (UTC)[reply]

Conservation of Energy

|<--F1--
|
|<--F2--
|
|

I have a question about the relationship between the linear and rotational analogs of classical mechanics. In space, if a force (F1) is imparted on the end of a rod, the rod would gain both translational kinetic energy and rotational kinetic energy, and the force would be accounted for as both a translational force and a torque. However, if an equal force (F2), is imparted on the center of mass, there would only be a change in linear KE since there would be no torque. However, these two results seem to contradict each other, and to violate the conservation of energy: despite the same force, the example of F1 gains additional (rotational) KE. Thus, the first time I saw the problem, I thought F1 should be divided into two components, one to calculate linear force, linear momentum, and linear KE; and the other to calculate torque, rotational momentum, and rotational KE. ~~Yet I know this is not true from what I have learned~~(correction: see my comments below). How can one rationalize the extra energy due to the "double-accounting" of force in the example of F1? Does the force act over a greater distance? Or is there more energy lost to heat? --JianLi 17:04, 22 January 2006 (UTC)[reply]

Energy is force integrated over the path. They don't move the same way in F1 and F2, so they don't have the same energy. Your mistake is in assuming equal force is equal energy. --BluePlatypus 19:55, 22 January 2006 (UTC)[reply]

I think if there were no friction and no other forces, F1 by itself would impart no torque to the rod. The only way F1 could impart torque is if there were a hinge or something to apply a force in the opposite direction somewhere else along the rod. —Keenan Pepper 20:01, 22 January 2006 (UTC)[reply]

Wouldn't inertia have something to do with it? Tzarius 20:19, 22 January 2006 (UTC)[reply]

BluePlatypus's explanation is correct. There's no "double accounting" here. Total KE is the integral of (v^2)dm over the rod in both cases. Separation of translational and rotational energies is just a matter of convenience so that we don't have to integrate every time. Equal force doesn't mean equal work. There's no "Law of conservation of force" either. The moment (torque) on the rod is independent of any friction. (A perfectly free bar hanging in vacuum will also acquire rotational KE when hit by a bullet at one end.) deeptrivia (talk) 20:29, 22 January 2006 (UTC)[reply]

Assuming the object is in space, it would only rotate about it's center of mass if pushed on the end as in the case of F1. Thus, it would only have a torque in that case. StuRat 21:22, 22 January 2006 (UTC)[reply]

No, its center of mass will also have an acceleration equal to F1/m. So it will translate also. deeptrivia (talk) 21:26, 22 January 2006 (UTC)[reply]

No, it won't. Try it with a ruler on a table and you will see it just spins. StuRat 23:29, 22 January 2006 (UTC)[reply]

Unless we are talking about different things, I'm pretty confident that the center of mass of any system with mass m will accelerate at F1/m if there is a net external force F1 on it, regardless of where the point of application of F1 is. There are no exceptions to this rule. deeptrivia (talk) 00:00, 23 January 2006 (UTC)[reply]

And I am quite sure you're dead wrong. The best evidence is just what the poster of the question asked about. If the same linear motion is imparted in both cases, but in the one case a rotational motion is also imparted, then you would have the translational plus the rotational kinetic energy in the one case and only the translational kinetic energy in the other case, and the two energy totals would be different. You can't put the same amount of energy into two systems and get a different amount back out. StuRat 00:09, 23 January 2006 (UTC)[reply]

StuRat, you are incorrect about this. You are also incorrect about conversion of mass into energy. Why so many wrong answers? -lethe ^talk 22:13, 24 January 2006 (UTC)

The point is, applying same force (at different points) does not imply putting in same amount of total energy, and therefore there's no paradox. This is the reason why it will be harder to keep a long heavy rod horizontal by holding it at one end compared to holding it in the middle (The translational KE in both cases will be the same; while the rotational KE will not be the same, since the moments created by these forces are not the same. To apply the same force F1 on the end of the rod for T seconds, the external agent will have to do more work compared to applying the same force at the center of mass. In Newtonian mechanics, you transfer to the center of mass a force whose line of action does not pass through the center of mass, and add a moment equalling rxF on the system. I teach rigid body dynamics to undergrad mechanical engineering students, and I know many students find this counterintuitive. deeptrivia (talk) 01:14, 23 January 2006 (UTC)[reply]

I still say the force on the end wouldn't cause it to spin. The reason the ruler on the table spins is because friction drags the other end back in the opposite direction, creating a force couple. In a vacuum it would move in a straight line. —Keenan Pepper 00:55, 23 January 2006 (UTC)[reply]

If that was true, then no objects in space should be spinning. The reason they are spinning is that mostly dust and gas particles impacted them off-center during their formation. StuRat 07:41, 23 January 2006 (UTC)[reply]

Wait, now I'm not so sure. This seems like it should be such an easy problem... —Keenan Pepper 01:07, 23 January 2006 (UTC)[reply]

This is a tricky question. First of all, a force on the end of a ruler in the absence of friction will certainly result in both rotation and linear motion. The linear motion should be the same regardless of where on the object it's applied, so there does appear to be a paradox. I'm going to consult with some of my fellow physics grad students and get back to you on this later. -- SCZenz 00:59, 23 January 2006 (UTC)[reply]

Ok, the linear motion isn't the same. Some of the energy/momentum goes into rotation. An analagous situation is that an object rolling down an incline ends up going slower than an object sliding down the same incline without friction. -- SCZenz 01:04, 23 January 2006 (UTC)[reply]

Correct. If the force is applied at the center of the rod, then 100% of the energy will go into translational motion and 0% into rotational energy. And if the force is applied tangent to the rod at the end of the rod, 100% of the energy goes into rotation and 0% in translation. Of course, in the real world you can't apply a force at a point, but must apply it over a range, so, since the force can't all be applied exactly at the end of the rod, some small translational motion would result. StuRat 07:36, 23 January 2006 (UTC)[reply]

Why do you say that? To have no translation would appear to me to violate conservation of momentum. I'm pretty sure there is still a substantial amount of translational motion. -- SCZenz 07:52, 23 January 2006 (UTC)[reply]

How does it violate conservation of momentum ? Translational momentum can be changed into rotational momentum with no violation. StuRat 08:03, 23 January 2006 (UTC)[reply]

"Translational momentum can be changed into rotational momentum with no violation." No. Linear momentum and angular momentum are separately conserved. deeptrivia (talk) 13:43, 23 January 2006 (UTC)[reply]

Wrong. If that was the case the linear momentum of wind could never drive the rotational momentum of a windmill. It does however, and removes some of the linear momentum of the air in the process. In another example, the translational momentum of cyclinders in an internal combustion engine is converted into the rotational momentum of the drive shaft. StuRat 16:45, 23 January 2006 (UTC)[reply]

It's the angular momentum of molecules in the air about the center of the windmill fan that makes it work. A body need not rotate to have angular momentum, which is simply r x mv, where r is the vector joining the CM of the body and the point wrt which angular momentum is conserved. If wind turbine blades were so designed that this angular momentum cancels out, then it won't rotate no matter how high the wind speed (how large the linear momentum.) deeptrivia (talk) 18:51, 23 January 2006 (UTC)[reply]

An element of air travelling at a velocity v i located at a distance d from the ground will have an angular momentum d j x mv i = -dmvk wrt the ground.

deeptrivia (talk) 20:55, 23 January 2006 (UTC)[reply]

You're looking at it in a strange way, measuring the angular momentum of the air relative to the windmill. A more normal way to look at it is relative to the ground. In this view, the air has no rotational momentum, but only linear momentum, and loses some of this as it imparts rotational momentum on the windmill. StuRat 20:33, 23 January 2006 (UTC)[reply]

Of course, it would have angular momentum wrt the ground too. The easiest way to calculate the angular acceleration of the wind turbine is to calculate angular momentum wrt the CM of the turbine. deeptrivia (talk) 20:55, 23 January 2006 (UTC)[reply]

In this case there is an external force (F1 or F2) acting on the system in question (the rod). Momentum–linear or angular–won't be conserved. TenOfAllTrades(talk) 14:35, 23 January 2006 (UTC)[reply]

Yeah, I was talking of a system that includes the agent that applies the force. If you exclude it, you can say that the rate of change of linear momentum will be equal to F1, and the rate of change of angular momentum about the center of mass will be (separately) equal to F1*L/2, assuming the CM is halfway the length. deeptrivia (talk) 15:27, 23 January 2006 (UTC)[reply]

Hi, this is the original poster. Thanks to everybody (especially Keenan Pepper, deeptrivia, and StuRat) for responding. I haven't read all your responses yet. However, I see some pretty heated arguments, and I just wanted to clarify what I know for sure (as these answers are from the 1998 Advanced Placement Physics C Test (mechanics section, second free-response)

In the situation of F1, its center of mass would translate, as deeptrivia said.
In the situation of F1, it would also rotate, despite the lack of friction.

The reason there is so much debate over this, I think, is that it's hard to imagine what it is like in space since we draw heavily upon our experience on earth, where friction and gravity are big factors. That's why the ruler example that StuRat cited is not an accurate simulation of F1. Instead, try dropping a pen above a desk, and, as it is falling, hitting its end with with your finger in a motion parallel to the plane of the table. That way, friction would not be a factor, and also, gravity would be acting perpendicular to the force you impart, so it wouldn't affect it. As you can see, it gains both translational motion and rotation. --JianLi 03:34, 24 January 2006 (UTC)[reply]

(m)<--v--(m)
 |
 |<--v--(m)
 |
(m)

FYI, I looked at the original AP question, and it does not mention force at all, as it is a conservation of momentum problem involving collisions and velocity, so what I said in my original post, about what was "true," is not necessarily right (the amended diagram is above). That said, the previous two points that I numbered and bolded still apply. In this case, both collisions gain equal linear momentum/KE, and the upper case also gains an angular momentum/KE The AP problem is: there is a massless rod of length "l" with spheres of clay on the ends (each with mass "m") kinda like a barbell. Another sphere of clay with mass "m" and velocity "v" hits the construction perpendicularly and sticks. In the first example, it hits it in its center of mass, and the second example it hits at its end (striking one of the other spheres). Remember, in both examples the moving mass sticks to the barbell. Obviously, the two systems have the same initial KE. However the rod in the second example gains rotational KE as well as the translational KE that the first rod also gains. Why? This is because in both cases, KE was lost to heat, etc. due to it being an inelastic collision (since the clay stuck), and more KE was lost in the first collision than in the second, which explains why the first collision had enough energy to have rotational KE too. Like I said, I'm not sure how this relates to Force, as this problem only mentions velocity, and I think it could be any quantity of force, depending on how much time the collision took ( $m\Delta \mathbf {v} =\mathbf {F} \Delta t$ ) --JianLi 04:12, 24 January 2006 (UTC)[reply]

Ignore my previous responses, they're dead wrong. =P The fundamental thing is that the angular momentum of an isolated system about any point is conserved independently. The origin of the coordinate system does not have to be at the center of mass. So, a mass moving in a straight line has angular momentum about any point not on the line, and a single force has torque with respect to a point not on its line of action.

So I think the solution to the energy conservation problem is that the system in which the ball of clay is heading toward the end of the rod has more rotational kinetic energy to begin with, because the ball of clay has angular momentum with respect to the center of mass of the system. Does that make sense? —Keenan Pepper 18:04, 24 January 2006 (UTC)[reply]

Your idea about the ball initially having rotational KE is interesting, but, if you're trying to explain where the "extra" rotational KE at the end came from, it's not even necessary. As I wrote above, both systems actually lost energy due to heat, etc. in the inelastic collision; it's just that the first system lost less energy, so it had enough to have rotational KE - JianLi

Total initial E = 1/2 mv^2

Total final E

for midpoint collision = 1/6 mv^2
for endpoint collision = 5/12 mv^2

As you can see, there is no need to explain "additional" rotational KE, as E was actually lost to to an inelastic collision in both cases -JianLi

Ok, with the new clay ball model there would be some changes. In addition to delivering a certain amount of energy, as the force would, the clay balls will also increase the mass. In the case where the clay ball hits at the other clay ball on the end, the rod will rotate about the NEW center of gravity, taking the new ball's mass into account. Since it doesn't hit exactly at the end, but rather at 1/2 the end ball's diameter from the end, some linear motion will also be imparted. StuRat 19:39, 24 January 2006 (UTC)[reply]

By mentioning the part about "1/2 end ball's diameter," are you implying that there would be no translational motion at all if it were hit "exactly at the end?" If so, I'm pretty sure that's wrong. As deeptrivia said, "the center of mass of any system with mass m will accelerate at F1/m if there is a net external force F1 on it, regardless of where the point of application of F1 is. There are no exceptions to this rule." And the AP answers support this, stating that the final translational momentum and KE will be the same in both of the two cases, so I don't think the amount of translational motion depends on how far from the end it hits the rod (assuming that it does hit the rod, of course). Also, physics problems at this level are usually very simplified; in this problem, the balls are assumed to be point masses anyway since we are not given their diameters.-JianLi

black hole

what is a black hole and is time travel possible with the help of a black hole? — Preceding unsigned comment added by 61.1.217.105 (talk)

Welcome to Wikipedia, the free encyclopedia! Did you know you can use the search bar at the left side of your screen to find answers to most of your questions? Try searching for "black hole" and "time travel". --David Iberri (talk) 17:14, 22 January 2006 (UTC)[reply]

Try time travel and black hole Gerard Foley 17:24, 22 January 2006 (UTC)[reply]

It's not possible using a black hole--they only have stuff go in, not out--unless you count travelling into the future faster than you would otherwise. It may be possiblse using a wormhole; see the physics section of the time travel article. -- SCZenz 00:56, 23 January 2006 (UTC)[reply]

From the wormhole article: "In physics, a wormhole is a hypothetical topological feature of spacetime that is essentially a 'shortcut' through space and time." and "Wormholes known as Schwarzschild wormholes or Einstein-Rosen bridges are theoretical bridges between areas of space that are thought to be found in the center of a black hole and white hole, joining two universes." DirkvdM 09:37, 23 January 2006 (UTC)[reply]

See What is a black hole, really?, Time Travel - Fact or Fiction? and other topics from the Usenet Physics FAQ. – b_jonas 23:34, 23 January 2006 (UTC)[reply]

Maxcy-Silberston curve

What is Maxcy-Silberston curve that is used in Automobile production industry? I just know that it is related to mass production system, but want to know more about it. I would appreciate any help on this topic. Thanks.

eye compared to a camera

Can the resolution of the human eye be (roughly) described in megapixels the way digital camera resolution is expressed?

Digital cameras (and conventional ones too) mimic the retina using color sensitive receptors for red, green (x2), or blue on a CCD, which is much bigger than the retina. Each receptor functions as both a rod (since each one captures luminosity, regardless of color) and cones (specific to its named color only) at the same time. The receptors send this information to a CPU, which either compresses the info (like JPG) and saves it or just saves it (like RAW). A 3.1 mega pixel camera has 3.1 million red, green (x2), or blue receptors.

My biology text book says, “Input from about 125 million rods and cones synapses on bipolar cells, which send the signals to just one million ganglion cells.” Does that mean that the retina (our body's CCD) has a resolution of 125 mega pixels which is then compressed to a 1 mega pixel image sent through the ganglion cells?

For a digital camera to capture an image as crisp as the human eye can capture, would it need to be 125 mega pixels per retina sized area of its CCD?

Of course, we would need a matching printer, right? What if we were using our fictitious camera as a bionic eye and plugging it directly into the optic nerve? Would we only need one mega pixel per retina sized area on our CCD or would we need the 125 mega pixel with a CPU to compress the info down to 1 mega pixel? --TheLimbicOne(talk) 18:24, 22 January 2006 (UTC)[reply]

This thought is somewhat developed in this website. Take a look. ☢ Ҡieff⌇↯ 22:32, 22 January 2006 (UTC)[reply]

Note that they have implanted electrodes into the visual cortex of the human brain, which do allow limited vision for the blind. At present it's quite low resolution, like 100 pixels, though. StuRat 23:26, 22 January 2006 (UTC)[reply]

Information technology

it's information, it's technology, why it's information technology! --Noodhoog 20:27, 22 January 2006 (UTC)[reply]

Why not? It's technology of information: putting things like Information theory to practical use. Compare it with Informatics, which is also known as Information science. deeptrivia (talk) 04:53, 23 January 2006 (UTC)[reply]

car radio narrowband filter

I would like to get a filter installed in my car radio to drastically improve its adjacent channel selectivity (FM). I am willing to give up some audio quality, but I am downright sick of hearing static-filled copies of adjacent channels when tuning to a weak station. I don't know how to mess with the radio myself, so where can I go? I live in Arkansas. — Preceding unsigned comment added by 14:11, January 22, 2006 (talk • contribs)

Have you tried taking your car (and your radio) to a mechanic? He/she might be able to give you better help, depending on your model of radio... — QuantumEleven | (talk) 09:56, 23 January 2006 (UTC)[reply]

I don't think a mechanic would be of much help here, unless you'd already found a filter and just needed someone to install it. Anyway, I don't think there's generally a whole lot you can do to increase selectivity on a car stereo; it's either got decent selectivity built-in or (more likely these days) it doesn't. You're probably going to be better off just buying a whole new radio. I'd suggest visiting the Crutchfield site (crutchfield.com) or calling them at 800-955-6000. Supposedly they're very good on the phone and willing to spend the time to help you figure out what you need. If they can't find a narrowband filter for you, they should at least be able to tell you which car stereos have the best selectivity in your price range. (Disclaimer: I've never dealt with Crutchfield myself.) Alternately, you may want to post a question on the CarStereo.com forums. --Aaron 15:58, 23 January 2006 (UTC)[reply]

Brain transplants!

What stops people from transplanting one brain into another body? If you could connect everything to the spinal cord and other attachments, why wouldn't it work? And what would happen if you could theoretically put a man's brain into a woman's body?

I think the question is what stops people from trying, because noones tried on an unclassified basis. Read article, for instance (and here's a funny gag). Karol 20:24, 22 January 2006 (UTC)[reply]

All the nerves and blood vessels would need to be reattached without any air bubbles in the blood vessels. Provided you could find a donor with the exact same skull geometry it seems possible (after vast advances in medical technology). However, the donor would have had to die from a brain ailment, or else the donor body would still be damaged after the transplant. And, since the brain is the essential part that is "you", it would be more proper to call it a body transplant. I imagine the brain would need to adjust to differences in the new body, such as differences in height which would require adjusting how you walk, for example. Immunosuppressants would be needed to prevent rejection, as in all transplants. A gender change seems like it would work, as parts of a body of one gender more or less match one-to-one with the other gender (for example, the nerves in the penis would match the nerves in the clitoris). StuRat 21:07, 22 January 2006 (UTC)[reply]

We really need an easy indexing system or a new set of ref desk editors, as this is another one we did to death about 2 months ago. alteripse 21:37, 22 January 2006 (UTC)[reply]

Read I Will Fear No Evil for a fictional take on brain transplants. —Keenan Pepper 22:04, 22 January 2006 (UTC)[reply]

See also brain transplant and notice how you end up under a different title (as StuRat pointed out). About the gender mixing, since much (how much?) of one's gender is determined by hormones and (most?) hormones are produced in the brain, the body would probably adapt over time (growing breasts or a penis and that sort of thing). DirkvdM 10:46, 23 January 2006 (UTC)[reply]

I disagree. The sex hormones estrogen and testosterone are primarily produced by the ovaries and testicles, respectively. This is why castrated males (eunuchs) don't appear or sound very masculine. StuRat 12:27, 23 January 2006 (UTC)[reply]

As to the ethical issue raised in the BBC article, the only objection is that it's, well, grotesque and, ehm, unethical. So it's unethical because it's unethical. No real reason is given. I't just a matter of getting used to. People don't argue anymore that flying is bad because God didn't give us wings. We've gotten used to that it don't give it a second thought anymore. Anyway, if it's ok to transplant every single organ individually, then what's wrong with transplanting them all in one go? It's the logical next step. Of course, it wuld be nice if it were possible to connect all the nerves, so we'll have to wait for that development in medical science, but muy bet is that that is just a few decades away. I'll see this happen in my lifetime. And I hope for Hawking that he will too. :) DirkvdM 11:00, 23 January 2006 (UTC)[reply]

Nobody ever thought that if someone was given a Brain Transplant that they wouldn't really be the same person anymore. They would have the Knowledge and memories of the person they got the brain from. This is only the case in bodies that get new brains, not if someone wants a new body. But then whose to stop scientist from creating Robots with human brains?

And this is where it gets really interresting. Suppose we could make an interface between a brain and a computer so that the two could communicate so well they ultimately become one entity. Then the person would have access to all sorts of sensors and actuators that go way beyond the capabilities of the carbon based entity it was first restricted to. And of course the size of the computer would be in principle limitless. So the old brain would become an insignificant part of the bigger entity. And when that old brain dies, that would be like a minor brain damage. Result: ETERNAL LIFE! (Sorry about the shouting, but this is a big one, right? :) ) DirkvdM 18:38, 24 January 2006 (UTC)[reply]

Claims of Scientific Evidence Against Evolution

In your website, you said talked about scientific evidence for Darwin's theory of evolution.But then, how come I've heard some Christians and creationists say that there is evidence against it?I'm confused!How can there be both evidence for evolution(or any other theory) and against it? What are these so-called evidences against evolution that many Christians claim to exist and are they really evidences against it?Please make an article in Wikipedia about these claims of evidence against evolution!! — Preceding unsigned comment added by 220.245.178.131 (talk)

There is a huge amount in wikipedia on these topics. Start with the Creation-evolution_controversy article and it will lead you to others. David D. (Talk) 21:29, 22 January 2006 (UTC)[reply]

Note: the same user asked exactly the same question here just over a week ago (see [4]). —David Wahler (talk) 21:32, 22 January 2006 (UTC)[reply]

I appreciate you pointing that out. I'll be more alert in the future. David D. (Talk) 21:33, 22 January 2006 (UTC)[reply]

Here is the archived version of the previous time it was asked. A lot of good answers. David D. (Talk) 21:41, 22 January 2006 (UTC)[reply]

Note that just about any theory has evidence for and against it, you must go with the majority of evidence to determine if the theory is reasonable or not. For example, the presence of pyramids in both Egypt and South America could be taken as "evidence" that the ancient Egyptians colonized the Americas. However, there is far more evidence that they didn't (different style pyramids, different time frames, low technology level of Egyptian sailing vessels, different genetic profiles of the individuals, different skeletal features, lack of historical accounts, etc.). StuRat 23:18, 22 January 2006 (UTC)[reply]

Occam's Razor supports this. freshgavin TALK 01:00, 23 January 2006 (UTC)[reply]

Scientific theory isn't a democracy. You don't go with the 'majority' of the evidence, you go with all the evidence. Also, it is impossible to gather evidence for something that isn't true unless the evidence isn't any good, or you're misusing it. This is, presumably, what the creationists are doing, and what you would be doing if you linked the pyramids in one place to the pyramids in another without actually bothering to study their design or age. Black Carrot 03:12, 23 January 2006 (UTC)[reply]

You will almost never find that all the evidence points in one direction only. One reason is that the evidence can be wrong (studies can either be intentionally faked or have an unintentional error in them). Another possibility is that the theory is good, but needs a little tweak to perfect it. For example, the heliocentric model of the solar system originally had all the planets in circular orbits. When this didn't quite match the observed orbits this could be taken as "evidence the heliocentric model of the solar system is wrong". However, the theory was correct, it just needed to be altered to have the planets in elliptical, rather than circular, orbits about the Sun. In medical studies, it is quite common to have some studies show a medication is effective while others show it is not. The "majority rule" method must be applied there. StuRat 08:57, 23 January 2006 (UTC)[reply]

No scientific theory is perfect; every nontrivial scientific theory has unexplained aspects and unanswered questions. Science is always trying to refine its theories and answer new questions that come up. If there are currently a few unanswered questions or unrebutted critiques of evolution, this does not mean that evolution is "troubled" or "in doubt" as a theory. Quite the contrary: it means it's a healthy, vibrant theory. (It would be extremely unusual if a theory as complex as evolution did not have a few unanswered questions or unrebutted critiques at any given point in time.)

What's important to realize is that most of the allegedly "controversial" aspects of evolution which are bandied about like so many brickbats by evolution's latter-day critics are not, in fact, brand-new hitherto-unasked impossibly hard questions which scientists can't answer. They are or might once have been good questions, but they're questions which were asked and answered decades or centuries ago. Our current understanding of evolutionary theory does not quail before these questions: it embraces them; it's happy to answer them; it owes its current form to the fact that it has successfully addressed and answered them.

In particular, the notion that life is "too complex" to have arisen by chance, and "must obviously" be the work of an intelligent designer, is a very, very old one. It was most famously expressed by William Paley over two hundred years ago, in 1802, but it goes back at least to Cicero in ancient Rome. If you accost a modern evolutionary biologist and suggest that life is "too complex" to have arisen by chance, he is not going to slap his forehead and say "You're right! I never thought of that! Our whole theory must be wrong!". Instead, he will explain (if you're patient and open-minded enough to listen) how the available genetic diversity and mutation rates and natural selection mechanisms are more than adequate to explain the current complexity of life as we know it, given the millions of years it's had to evolve. It's true that this is a surprising result, and that it contradicts intuition. Many scientific results are like that. But the evidence behind the theory and the math that ties it together are unshakable. Steve Summit (talk) 03:57, 23 January 2006 (UTC)[reply]

Paley's viewpoints were, of course, most famously attacked by Richard Dawkins in his book The Blind Watchmaker. However I think you will find that the math is far from 'unshakeable'. There are plenty of questions still to be answered there. We know very little about how complex structures evolve (if they do). You will find, if you look, lots of quotes from evolution apologists saying things like "if all scientists don't get together and insist that all the problems of evolution are solved, then the people will stop believing in it and that will be very bad for science". DJ Clayworth 16:10, 24 January 2006 (UTC)[reply]

Wanna give an example?--Fangz 00:43, 25 January 2006 (UTC)[reply]

When my good old Occam designed the Pyramids, he told me about his deep horror for proofs.

"It is something like advertising, quoth he, that makes you believe that you've perused every reason and took your decision out of free will. Or a confession obtained under torture. Nauseous human mind!

Science and law work under the proofocracy. That's their method, and there is good reason for that. Science recognises no evidence, as every proof is only local or temporary and must be falsifiable. Law needs to produce results, sometimes too quickly for true justice." I agreed. --DLL 19:27, 23 January 2006 (UTC)[reply]

Love-causing Hormones

I've heard that love and sexual attraction are caused by chemicals in our brains called hormones or pheromones.But the question is, how do those hormones get to determine exactly WHO you fall in love with?For example, let's just say that a single man often meets and comes in contact with 3 single women.If then, what in the hormones determine which one of these 3 women hormone makes him falls in love with?Is this simply a matter of pure,random chance or is there an unknown force or influence that determines it?I don't like the idea or possibility that that might be something or someone "out there" determining who you and me marry and fall in love with! — Preceding unsigned comment added by 220.245.178.131 (talk)

I think the hormones and chemicals come after you see someone you like and fall in love,not before.and you like them because of their looks, personlity or both.--Cosmic girl 22:22, 22 January 2006 (UTC)[reply]

That's right. Some of the visual factors are: symmetricality of the face, the waist to chest ratio, sharp vs soft facial features, etc. Women are attracted to different men depending on where they are in their monthly cycle, sometimes going for a more masculine look, sometimes for a more feminine look. StuRat 23:07, 22 January 2006 (UTC)[reply]

I second the above, with the obvious correction that strictly speaking hormones don't start working after you fall in love - they're working before and during too and they're part of the reason.

I'd also add that it's certainly not a matter of chance, but nor is it truly a matter of free choice. Obviously we can't fall in love with people we can't somehow get in contact with, but we can't help where we're born - that's chance. People also only very rarely fall in love with the profoundly disfigured because they just can't fine them attractive - but this isn't chance or freedom; this is hardwired into our brains. Point is, there are numerous variables that determine who we fall in love with and how successful we are in our relationships. And yes, some of them are "out there" and beyond our control. --George 00:39, 23 January 2006 (UTC)[reply]

Go pick up an introductory social psychology text; it should have some enlightening (if not particularly fulfilling) insights on the topic. Ultimately, to some extent this argument gets back to free will. --Robert Merkel 06:34, 23 January 2006 (UTC)[reply]

My first thought was also that the hormones kick in after you meet someone. But my second thought (and probably what the questioneer asks about) is "what if you administer such hormones to someone when they are in contact with you?" In other owrds, which of the two (the meeting or the hormones) triggers the 'falling in love' feeling? In still other words, which way around is the causality with the love and the hormones? DirkvdM 09:51, 23 January 2006 (UTC)[reply]

I think we are confusing hormones and neurochemicals, hormones are there all the time and they are part of the reason why you fall in love, but neurochemicals start acting on your brain after you 'fall in love' or after you 1st see the person you like...I believe one of those neurochemicals or neurotransmisors is vasopressin and other is PEA and ... well they act on certain phases of 'love'. there is attraction first, then commitment and stuff...but a psychology book on love will answer almost all your questons like Robert Merkel said.--Cosmic girl 15:53, 23 January 2006 (UTC)[reply]

Though I can't find any reference to it in our article on French kissing, ISTR that one of the main physiological advantages of the French kiss is that it allows for an easy exchange of pheremones between partners. Grutness...wha? 23:11, 23 January 2006 (UTC)[reply]

Are pheromones for real? wow didn't know that. --Cosmic girl 19:55, 24 January 2006 (UTC)[reply]

The Big Bang Theory vs. The Law of the Conservation of Matter

I've heard that matter can neither be created nor destroyed.This is called the law of the conservation of matter.But now, scientists say that all matter in the Universe was created during the Big Bang.But how can matter be come out into existence in a "Big Bang" if matter can't created at all?Do you agree that the Big Bang theory violates the law of the conservation of matter? User:Bowei

You could start checking CP-violation ☢ Ҡieff⌇↯ 22:45, 22 January 2006 (UTC)[reply]

Another point, less accurate but a good model, is that if there was no moment in time before the Big Bang, then all matter/energy has existed in all moments of time. Conservation is still true.

And of course, matter is energy: matter can be destroyed, which 'produces' energy, and vice versa. -- Ec5618 22:50, 22 January 2006 (UTC)[reply]

You'd be better saying matter can be CONVERTED into energy and vice versa. The term "destroyed" is misleading. ☢ Ҡieff⌇↯ 00:32, 23 January 2006 (UTC)[reply]

Matter can be converted to energy (happens in stars every second of ever day) and vice versa. The Big Bang was an expansion, not an explosion. The real Big Bang Theory is quite complicated and would require some background in mathematics and physics to understand (which I really don't have), and any further explainations you will be given will likely be very simplified ones. Keep all of this in mind.Captain Jackson 00:52, 23 January 2006 (UTC)[reply]

You're talking about the laws of physics (as we know them), but those break down if you go further back than something like a millisecond after the big bang. From the big bang article: "There is no compelling physical model for the first 10-33 seconds of the Universe." Yes, I know this sounds lame, but there you go. Also, I doubt if one can say that all matter was created at the Big Bang. It, ehm, sort of 'emerged'? Anyway, I've got my own alternative to the Big Bang theory, but that's hardly been scientifically scrutinised. DirkvdM 10:02, 23 January 2006 (UTC)[reply]

To expand on that, remember that the laws of chemistry didn't emerge until there were atoms, and the laws which govern biological life didn't emerge until there were cells. So it makes sense that the laws of physics, which include gravitation, electromagnetism, and the strong and weak nuclear forces, wouldn't exist until there was matter and energy in the universe to begin with. Where did it all come from? It may have just always existed in a singularity somewhere, in other forms.

Also, I believe that the real law of conservation of matter states that matter can neither be created nor destroyed in a chemical reaction. The last four words are important. Captain Jackson 15:14, 24 January 2006 (UTC)[reply]

Einstein vs. Quantum Theory

I've heard that Einstein didn't like quantum theory.Why?

A famous quote of his is "I can't believe that God plays dice with the universe". In other words, he didn't like the random, unknowable part of QM. He preferred a universe which is predictable. Also, QM and Einstein's theories are somewhat incompatible, and it requires some effort to accomodate both. StuRat 22:59, 22 January 2006 (UTC)[reply]

Refs: Incompleteness of quantum physics [5] --Zeizmic 01:01, 23 January 2006 (UTC)[reply]

Weird

Is there any reason why a page would just close on me? I was trying to look at the article about the scanning tunneling microscope and it just closed before I could even read the first line... and since that happened like 4 times with the link in the question about atoms here at the science reference desk I just looked it up on google and clicked on the 1st link, and guess what?! it just cloesd on me again! what the hell? is this something paranormal? hahaha lol...I'm scared.--Cosmic girl 22:49, 22 January 2006 (UTC)[reply]

Probably just your web browser crashing. Which operating system and web browser software are you using? --Canley 23:01, 22 January 2006 (UTC)[reply]

I don't know what you mean I'm really dumb for computers, but I use windows xp and mozilla firefox and ... any page that has an article on that just closes whenever I try to read the article it has! no matter if it's wikipedia, or a physics page or the nobel prize page, every page closes on me when I try to read it...and this doesn't happen with other pages and has never happened to me before, ever.guess what? I can't even play the game about the scanning tunneling microscope at nobelprize.org! and I've played it before. basicly any page that involves that microscope just closes up on me and I'm not even that interested in it!--Cosmic girl 23:06, 22 January 2006 (UTC)[reply]

Ok it just stopped happening...so weird...--Cosmic girl 00:07, 23 January 2006 (UTC)[reply]

I think there is a bug in the current version of FireFox under Windows XP. If I have multiple browser windows open, sometimes FireFox changes from one window to another when I navigate to a new page. Are your FireFox windows closing or just going into the background behing another window? --JWSchmidt 03:01, 23 January 2006 (UTC)[reply]

That happened yesterday, it ONLY closed when I tried to read about the scanning tunneling microscope! only then! I swear...and it closed, it didn't go to the background... and no matter where I tried to read it, that kept happening...not even a game about it would stay open...it closed immediately. so strange this has never happened to me before. and it doesn't close all the time at the same time! sometimes it closes before the page even loads and other times it closes a couple of seconds after the page has loaded...it seems like it does so at will or something.--Cosmic girl 15:49, 23 January 2006 (UTC)[reply]

January 23

Why Copy Wikipedia?

Other than the public domain status, why are there so many websites out there copying articles from Wikipedia and putting them on their sites? What do they have to gain from it, just mirroring this site? Why are they spending money and wasting bandwidth doing it? Captain Jackson 00:41, 23 January 2006 (UTC)[reply]

As Wikipedia is non-profit, you can assume that the motivation for many is money, as most mirrors other than Wikipedia itself institute advertizing on their pages. freshgavin TALK 00:56, 23 January 2006 (UTC)[reply]

Yes, just money. Also, Wikipedia is not public domain, but GFDL. ☢ Ҡieff⌇↯ 01:53, 23 January 2006 (UTC)[reply]

Hey, come to my FREE encyclopedia! (and be exposed to my adverts) and get better grades in school!

Don't go anywhere else!!!

This is the place !!!!! (fine print hydnjo talk 02:38, 23 January 2006 (UTC))[reply]

Money aside, many people have the will to create a website but don't have the creativity to, like, actually create any real content. So they go find some free, "public domain" content (or what they imagine to be public domain content) and copy it to their fledgling site. Usually, in an attempt to make their site seem attractive (and assuage whatever lingering internal pangs of guilt they might have) they will claim that their site somehow presents the copied information better, or otherwise adds value for their site's readers. (I don't know how many actual readers end up falling for this ruse in practice.) Steve Summit (talk) 03:20, 23 January 2006 (UTC)[reply]

Right, just like people put in google buttons on their pages for searches, and many news websites constantly quote nothing but AP and Reuters. Countless numbers of un-skilled internetians with ambitious dreams of attracting unknowing visitors. freshgavin TALK 06:21, 23 January 2006 (UTC)[reply]

This is a public site that is edited or added by any willing internet user. The beauty and popularity of Wikipedia articles is in its ever-changing and well-reviewed information. Although it is open content, copying the articles doesn't detract profits from the website, so I would promote the dessimination of information through wikipedia even if it includes copying and pasting simple articles on the websites of others.--192.160.130.12 21:36, 27 January 2006 (UTC)[reply]

Adobe Acrobat

Greetings:

Hello, I have a question concerning Adobe Acrobat. I was wondering how you can copy the slides onto a different document program. Or printmultiple pages of adobe into a single page. Answers, solutions and comments will be deeply appreciated. Thanks Shanna Zhang 129.97.237.131 03:17, 23 January 2006 (UTC)[reply]

I'm not sure what you're asking. Do you want to convert the text in an Acrobat PDF into another program (like Microsoft Word)? (Just cut-and-paste or export to RTF) Or 'place' the actual pages into a different document? (The only programs I know that can do that are Adobe InDesign and Adobe Illustrator). If you just want to print several pages on a piece of paper, go to the Page Setup and do it there. --Canley 06:41, 23 January 2006 (UTC)[reply]

As I understand it, you can only edit pdf files with Adobe's Acrobat. The reader is for free, but when you want to use the texts in any other way you'll have to pay through your nose for the editor. That's the ruse. I don't touch pdf's with a 3.05 m pole. Although it also seems that pdf's are good for printing (more wysiwyg, I believe). So it would make sense to convert a file to pdf before printing (and only then and not do any further editing with that version). But for that you'd need that editor and if you don't want to pay for it you'd have to get your hands on an illegal copy. But then you'd still indirectly be supprting a format that is generally to our disadvantage. DirkvdM 10:18, 23 January 2006 (UTC)[reply]

pdf's, in general, cannot be easily edited. Some are just bit scans, and some have printing commands sandwiched between every letter. If I am making a slide with pdfs, then I just use a screen-capture program, good enough for slides. Otherwise, you can print it and scan it. OpenOffice outputs pdfs but you can't bring them in again. It truly is a terrible format for re-editing. --Zeizmic 15:32, 23 January 2006 (UTC)[reply]

msssearchnet

My computer recently got infected with this annoying process on my windows XP operating system. I have tried forever to get it off but it can not. Are there any removal tools that will remove and kill the process. I have used spyware removal applications but they do not detect the process. I need help quick.

That's a nasty one! There's a forum where they discuss it here. Looks like you have to: kill four processes, delete eight registry values, unregister two DLLs, remove seven files and delete four directories. The steps are listed on the forum post. There is an automated tool to do it all but I haven't used it as I don't have this malware on my computer. Good luck! --Canley 06:52, 23 January 2006 (UTC)[reply]

You could use a program called HijackThis to delete this virus. You still need to direct the program by telling it what to remove, but it is safer than editing the registry yourself. Go here to see what files need to be removed. I have used HijackThis before, but not on this virus. Cybergoth 22:25, 24 January 2006 (UTC)[reply]

science project

hello! my daughter is doing a science project. to help her out, i have one quick question. What is the effect of temperature on a musical note? please respond to my question as soon as possible. thank you very much for your time.

The question is confusing. A musical note is, essentially, vibrating air. Are you thinking of the effect of temperature on musical instruments? If so, have a look at [6] and [7]. For the range of temperatures at which an instrument would be played, temperature won't ordinarily make a lot of difference with regard to pitch. - Nunh-huh 06:34, 23 January 2006 (UTC)[reply]

On the contrary, for wind instruments the effect is quite noticeable. The reason is because the speed of sound increases with increasing temperature, so on a hot day the frequency of the sound produced by a tube of air is higher than that produced by the same tube on a cold day. In other words, the same instrument will sound flat in cold air and sharp in warm air. —Keenan Pepper 07:19, 23 January 2006 (UTC)[reply]

Which is why you see salvation army trumpeteers in winter warm the mouthpiece of their instrument under their armpit (after they've let the spit drip out - they're a gory bunch, really). At least in US films - I've never seen such a band in Amsterdam. DirkvdM 10:23, 23 January 2006 (UTC)[reply]

In Canada, when it gets to 40 below, they warm the mouthpieces so their lips don't stick to it. Everybody knows that! :)--Zeizmic 15:26, 23 January 2006 (UTC)[reply]

When air is frozen, does sound propagate at all ? Does brrrrrish(!) air slow musical vibrations ? Also, what happens under bar pressures very different from average ones (pression & temperature are quite linked, but only in a closed volume). Is this the sense of the question ? --DLL 19:01, 23 January 2006 (UTC)[reply]

Another (related) point - though it's only relevant for music or sound heard at a great distance - is that I'm fairly sure sounds carry further in cold weather. I suspect that this is to do with the thermodynamics of the air it passes through. Grutness...wha? 23:02, 23 January 2006 (UTC)[reply]

I'm not sure about on a colder day specifically, but sound DOES travel further when there is a temperature inversion, see http://news.bbc.co.uk/1/hi/magazine/4521232.stm Modest Genius 00:14, 24 January 2006 (UTC)[reply]

Frozen milk

Due to absense of a fridge, I have to store milk between two frames of a window. When it's too cold the milk can freeze as a result. As you probably know, milk has quite complex structure of proteins, fat and water. What happens when the milk is frozen and then unfrozen back? Does it lose any properties, or it is reversible operation? Grue 07:37, 23 January 2006 (UTC)[reply]

The separation of the cream is the only effect I'm aware of. However, you really need to get a working fridge so your food doesn't rot when it gets warmer out. If you can't manage a full sized fridge right now, how about one of those "minibar" fridges ? StuRat 08:38, 23 January 2006 (UTC)[reply]

Also note that the UV light from the Sun might break down the milk. StuRat 08:41, 23 January 2006 (UTC)[reply]

Which is why cows keep their milk in handy light-proof bellypacks, shielding it from the Sun. So an alternative would be to keep a cow and drink straight from the source. Any excess milk, you could sell. And with that money you might buy yourself a fridge, so you you wouldn't need the cow anymore. DirkvdM 10:30, 23 January 2006 (UTC)[reply]

And if you had two cows, you'd have a famous joke. But, seriously, you could try small packets of that disgusting UHT milk that most of Europe apparently drinks (you don't need to keep it cold so it wouldn't need to sit in the window), or the even more disgusting powdered milk. Me, I'd scrimp and save as quickly as I could to buy some kind of fridge. --Robert Merkel 11:21, 23 January 2006 (UTC)[reply]

Condensed milk cans might be a good alternative. StuRat 12:20, 23 January 2006 (UTC)[reply]

I don't know anyone who drinks such milk. And I live in Europe. Actually, I had never heard of UHT before. The French don't seem to think much of it either, because else that carton wouldn't have the English abbreviation UHT on it (to the French that must look offensive). The article doesn't say where this stuff is used. Since you say Europe and that abbreviation is English, I suppose England? DirkvdM 19:27, 24 January 2006 (UTC)[reply]

The French probably expand it as Ultra-Haute Température. Not every French acronym is spelled backwards, you know. As for its popularity in various parts of Europe, I can't really say much. For what it's worth, here in Finland it is available in most stores, so there must be at least some demand for it. I've found it useful for keeping around in case I run out of normal milk, since unopened it lasts practically forever. —Ilmari Karonen (talk) 20:21, 24 January 2006 (UTC)[reply]

Well, not backwards, but probably TUH. DUH! :) DirkvdM 13:10, 25 January 2006 (UTC)[reply]

I, and many others I know, regularly freeze skimmed milk in the freezer to preserve it and cut down on trips to the grocery store. I've noticed no ill effects. DJ Clayworth 15:52, 24 January 2006 (UTC)[reply]

The butter article describes what ice crystals from chilling milk does to the fat globules. Since skim milk has less fat (typically 0.1%), it probably survives freezing better. Cybergoth 22:29, 24 January 2006 (UTC)[reply]

Soy milk also lasts longer than cow milk with minimal refrigeration. I'm not sure what effects freezing has on it though. StuRat 17:37, 25 January 2006 (UTC)[reply]

It makes it cold and hard! freshgavin TALK 04:01, 27 January 2006 (UTC)[reply]

Speed of light/Time travel

After reading the previous intriguing topics, an old question popped up in my mind. If we could [hypothetically] go into space at twice the speed of light, would we be able to see the light of historical situations, like we see stars as they were a long time ago? Let's say we were going facing the earth, wouldnt it look like rewinding a moving image? Is this possible? 83.5.204.185 07:43, 23 January 2006 (UTC)[reply]

Yes, that's exactly what it would look like. Not only would it look like that, but according to the Theory of Relativity, you really would effectively be travelling through time. That theory also places rather formidible obstacles to going faster than (or at) the speed of light; in fact, it's believed to be impossible. -- SCZenz 07:49, 23 January 2006 (UTC)[reply]

Impossible for people, yes, for fundamental particles like tachyons, no. StuRat 08:44, 23 January 2006 (UTC)[reply]

... You mean hypothetical particles. ☢ Ҡieff⌇↯ 08:48, 23 January 2006 (UTC)[reply]

Yes, that's what I meant, good catch. StuRat 09:16, 23 January 2006 (UTC)[reply]

Also, if tachyons exist, they could never slow down to below the speed of light, so they wouldn't be of much use to us. — QuantumEleven | (talk) 09:44, 23 January 2006 (UTC)[reply]

Also one of those 'brilliant ideas' from my childhood. But then I realised you'd need a fairly strong telescope, to put it mildly. However, if this makes you travel back in time, you could just double back and return at some time in the past. In which case you'd better make room for a rather sizeable turning circle. :) But then how to get back to your own time? (What's the point i knowing this if yo can't share it with your mates?) I suppose that once you've figured out how to travel faster than the speed of light, you'll also know how to go slower than standing still. DirkvdM 10:37, 23 January 2006 (UTC)[reply]

As far as I understand it, there would be no formal travelling back in time. It's just a four-dimentional space, so-called "space-time". There is a notion of event, it's just a point in 4D space (c*t,x,y,z). Still there are no tricks. A speed is, as usual, defined as little change in 3D distance, devided by a corresponding change in time. If you say the body is moving, it automatically means that the time increases (just by definition).

One of the postulates of special relativity sais that no interactions can spread faster than c. Thus, two events, near in time, but with much enough distance between them are not cause-effect related. In Newtons mechanics, which we ordinarily use (even in our language), "A occurred earlier than B", is equal to "A was a cause, B is effect". In special relativity, these notions are not equal. So, yes, if you manage to travel faster than light, you will break cause-effect relation and will be able to see light from past of the Earth; poetically, you can call it travelling back in time, but formally, it isn't.

The "real" tricks arise when you go to a moving reference frame. It's because "space-time" is pseudo-euclid, that is, if the vector between two events is (c*t,x,y,z,), the value that remains constant is not (c^2*t^2 + x^2 + y^2 + z^2) as one would expect, but (c^2*t^2 - x^2 - y^2 - z^2). ellol 12:31, 23 January 2006 (UTC)[reply]

Going back to your own time the easy part. Just travel for a while close to (less than) the speed of light (the closer the better) and thanks to the relativistic effects you can travel into the future without experiencing most of the time in between! freshgavin TALK 04:29, 25 January 2006 (UTC)[reply]

Yeah, but that's just travelling into the future the way we all do, simply through the passing of time. It's just that time passes at different speeds in different referenceframes, creating the illusion of time-travel. But the notion of travelling back in time by exceeding the speed of light (if that were possible) is (would be) more than poetic. It would be quite real. I think. But then, as with everything, I am no expert in the field. DirkvdM 13:28, 25 January 2006 (UTC)[reply]

I'm pretty sure none of us are experts in this field : ). Anyways I don't see the difference between the illusion of travelling in time, and actually travelling. The relativistic effects of travelling close to the speed of light are hardly an illusion, and if you could do that you would, quite actually, move forward in time faster than you would if you couldn't. If emerging 50 years later not having aged and having felt the passage of no time doesn't constitute time travel into the future, than I don't know what does (all poetics aside). freshgavin TALK 07:05, 26 January 2006 (UTC)[reply]

DirkvdM, thank you, it gets interesting :) So, let's consider you flying with the speed 2c. What then? We have to distinguish two notions: time in our, "not moving" system (call it t), and time in your system (call it T). So, let's write down one of the basic laws: that is, invariance of interval in all reference frames. Square of interval is s^2=(c^2*t^2 - x^2 - y^2 - z^2), if t, x, y and z are time and spatial distances between two events. Let you be moving along x axis; t and T are time distances between two moments; and x is distance you travelled in our system between those moments:

s^2 = c^2 * T^2 (you are not moving in your system)

s^2 = c^2 * t^2 - x^2 = c^2 * t^2 - (2c * t)^2 = -3 * c^2 * t^2 (in our system your velocity is 2c, => you travelled distance t*2c)

In result we have T^2 = -3 *t^2, => T=i*sqrt(3)*t or T=-i*sqrt(3)*t

Hmmmm... Really, it makes no sense, except confirming once more, that since we used wrong suggestion about you travelling with velocity more than c, we got senseless answer.

Btw, difference between time and casuality is well explained at Special_relativity#Causality. ellol 17:00, 27 January 2006 (UTC)[reply]

Two questions!

Two questions, rolled into one nifty little asking box thingamajigger.

What does glycine have to do with photography? It was listed in the photography chemicals category before I removed it, and as it says "it is not optically somethingorother" (paraphrasing), I fail to see how it could possibly be related in any way. (It's not a homework question; I just want to know if I screwed up.)
Why is it that whenever a male ejaculates they have the urge to urinate soon after?

As you can see, these are very different subjects. Cernen Xanthine Katrena 11:05, 23 January 2006 (UTC)[reply]

As for the second question, see urinary tract infection for a possible clue to what may be some sort of instinctual cleansing. Also, see the sex question which is right now near the bottom of the Ref. Desk/Misc. page. As for the first question, I believe, not sure though, that glycine was used to process that old fashioned film that cameras used to have before you kids and your computers came up with them there digital jobbers. Dismas|^(talk) 11:25, 23 January 2006 (UTC)[reply]

P.S. I did a little googling and came up with this which may give you some idea of what glycine is used for in relation to photography. Dismas|^(talk) 11:28, 23 January 2006 (UTC)[reply]

As for the 2nd question, I agree with the first response, but would add that urine is designed to be antiseptic, mainly due to it's acidic pH, while semen is designed to be "food" for sperm, which also makes it food for bacteria. Thus, clearing it out of the urinary tract fairly quickly is important to preventing infections. StuRat 12:11, 23 January 2006 (UTC)[reply]

Can I pick a couple of nits, sir? By most of our evidence, urine isn't designed to be anything. Second, it is aseptic rather than antiseptic. Third, it is aseptic not because of its mild acidity (there are many bugs that grow at mildly acid pH), but because it comes from a place with no bugs. Fourth, the mild STD and UTI protection afforded by postcoital urination is simply a washout effect: the flowing urine washes many new bacteria from the urethral orifice. alteripse 12:35, 23 January 2006 (UTC)[reply]

That explanation doesn't really work, as the semen also come from an aseptic place, so would have also "washed out" anything in the urinal tract. I stand by urine being antiseptic, and it has even been used as such in some cultures. Here, for example, are instructions on using cow urine for disease control:

http://oisat.org/control_methods/other_methods/animal_urine.html

As for my use of the word designed, you are indeed being picky. I use it as a shortcut for..."those animals with more antiseptic urine tended to reproduce more and pass on this trait to successive generations while those individuals with less antiseptic urine were less likely to pass on their genes". I sure don't want to have to say that more often than needed, so will only do so when forced into it. StuRat 16:25, 23 January 2006 (UTC)[reply]

And let's just say that UTIs in men, while thankfully uncommon, are pretty darn uncomfortable. To make a radical understatement. --BluePlatypus 15:13, 23 January 2006 (UTC)[reply]

The urine thing makes much more sense to me now that there has been...enlarged...debate over its antiseptic qualities. And as for the glycine bit, it's GLYCIN, not GLYCINE. Glycine is a bio-organic compound. Glycin is a chemical. I'll make the change right now, and thank you all for your help. 'Tis people like you guys that make the Reference desk the most bitchin' feature of Wikipedia. Cernen Xanthine Katrena 19:01, 23 January 2006 (UTC)[reply]

Whoa, watch the terminology! "chemical" is a really, really useless word. :) A better description of glycin would be "an aromatic organic compound" or "a nitrophenyl ether" and glycine as an amino acid. --BluePlatypus 20:44, 23 January 2006 (UTC)[reply]

Will AIDS spread like this????

This is in reference to a mail i got from one of my friends.. According to the mail a 10yr boy was infected with AIDS, because he ate food from a road-side dhaba(small hotel). The cook had a cut in his hand and he was infected with the virus(without his knowledge). So the blood from the cook's hand went to the food and it inturn went inside the boy causing the boy to be affected. Can this be true?? Can anyone plese confirm on this.. Thanks in advance.. --Arun Joseph

Sounds highly unlikely. If the blood ws cooked with the rest of the food, then the virus would be destroyed that way. If it fell on the food right before it was eaten, the virus could still be intact in the kid's digestive tract, but it's highly unlikely it could survive digestion and get into his bloodstream. I suppose anything is possible, say if he had a cut in his mouth and the virus got in that way, but this would be extremely rare. StuRat 12:03, 23 January 2006 (UTC)[reply]

All e-mailed health warnings are frauds. Valid information is disseminated by other routes. If anyone thinks this is too strong an assertion, please give a valid example of a true e-mailed health warning. alteripse 12:04, 23 January 2006 (UTC)[reply]

Thanks both of u.. I understand tht if the boy had a cut he cud be infected.. but even i cant believe abt the virus going inside the stomach and then the boy getting infected.. Thnkx much anyways.. If anyone has anything to add, please add.. and we cant just ignore such mails, Alteripse. Even if we think tht the e-mail may be fraud, we cant take risks.. and when it comes to things like AIDS, I believe no one will be taking chances.. Anyways thnkx much.. --Arun Joseph

You are welcome, but you should reconsider my advice. The nature of people and emails tells you that no new true health warnings are disseminated by email. You can ignore them. Do not propagate them-- it its the same as spreading false rumors, and people do cruel and stupid things in response to false rumors. alteripse 12:28, 23 January 2006 (UTC)[reply]

I will first of all emphasize my strong agreement with the comments above—health warnings distributed by email forwards are universally misleading at best, and usually are junk.

To address cases of this type...it is possible to transmit HIV (the virus which causes AIDS) by consuming someone else's blood, but it is quite rare. Usually the recipient has to have an open wound or sore on or in their mouth through which the virus can enter the new host; stomach acid is a very effective disinfectant and HIV isn't a particularly durable virus. The trace amounts of blood that might be passed on inadvertantly by a food handler also would tend to count against the likelihood of this particular story—if there is a visible amount of blood on the food, most people wouldn't take it.

As StuRat noted, any blood that got on the food before cooking would be sterilized by heat. HIV won't last very long even on cold foods—the virus would tend to dry out or be inactivated by food ingredients quite rapidly. TenOfAllTrades(talk) 17:48, 23 January 2006 (UTC)[reply]

It should be pointed out that the variants of viral hepatitis, which are bloodborne pathogens and can be spread through the same means as HIV, have historically appeared in population clusters that have been traced to infected food preparers. As such, the possibility of this type of food vector for HIV is not as beyond the pale as the responses would imply. However, there have been no citations I have been able to find of a single instance of this having occurred. This is no doubt due to the relative fragility of the HIV virus, and its relatively low infectivity (i.e., it requires a larger innoculum of live virus to cause active disease than do the various forms of viral hepatitis).

As for email being an unreliable form of health information-- that depends on its source. With due respect to Dr. Alteripse, his point is well taken, but email is already in use for transmission of vital health information (for example, as is the case in New York City's Health Alert Network). As electronic dissemination of information becomes more pervasive-- and it will-- there will be increasing need for authentication to safeguard the credibility of this vital means of communication. Until that becomes possible, however, it is wise to view any health warnings received by email with a generous grain of salt. It is always a good idea to see whether any warnings received by email are already documented as urban legends by checking Snopes.com.--Mark Bornfeld DDS 19:41, 23 January 2006 (UTC)[reply]

Thanks everybody. It really was very informative. Thanks to Wikipedia for this wonderful Q&A section. --Arun Joseph

There is a temperature range at which various life forms can survive. I once asked about risk of catching AIDS and other sexually tranmitted diseases from other people sharing a hot tub like at a hotel or health club. Then there are toilet seats, in public rest rooms, that might not be cleaned between one visitor and another. Basically what I learned was that most of these diseases need to be at body temperature, and not survive long outside of body temperature. Of course there are the other diseases like SARS that can be spread by someone coughing, then the garbage turns to dust that other people can pick up various ways and get that disease. User:AlMac|^(talk) 12:56, 24 January 2006 (UTC)[reply]

the hiv/aids virus can not live outside the body. it needs a specific temperature to remain active. nor can you contract it from a toilet seat. hiv/aids needs a port of entry into the body:ie cuts/lacerations/ulcers to be exposed and you must have direct

bodily fluid contact.

ports of entry also include lacrimol glands/tear ducts.

you can not contract hepatitis from toilet seats either. another case of a virus needing a constant temperature:(warmth)user:csi4u

Transmission and distribution

Why do we connect the neutral wire of the load to the distribution transformer neutral?
[unsigned comment 12:21, 23 January 2006 by User:59.92.119.214]

Well, there's sort of two ways of answering that. (I'm not quite sure what you're asking.)

What else would you expect to connect the load neutral to? You certainly wouldn't connect it to a hot lead of the distribution transformer!
The residential power delivery scheme commonly used in North America (I can't speak for other situations) is single-phase, three-wire, 120/240VAC. In this system, the last transformer in the distributon chain reduces the voltage to 240V, with a center tap, and with the center tap grounded ("earthed"). The end user can derive 120V by connecting across the neutral and one or the other hot lead; or, can derive 240V for higher-power motors and appliances by connecting across the two hot leads. (Ideally this would be explained and illustrated at Electricity distribution and I could refer you there, but I see that page needs work.)

Steve Summit (talk) 15:53, 23 January 2006 (UTC)[reply]

Windows CE .NET Compact Framework Application Development?

If there is some one out there developing .NET applications for Windows CE, you could help me. I'm evaluating the possibilities to migrate from PLC control in an application (which I would rather keep to myself which one it is) to using computers instead - and I've already done successful test "concept" applications on Windows XP using .NET Framework version 2. However, if it is possible to use Windows instead / in combination with Windows XP that could mean a cheaper/better overall solution.

I'm wondering what kind of development platform is necessary on the development PC, to develop applications for Windows CE, including deploying them to a smaller number of devices with preinstalled Windows CE 4.2 and/or 5.0. I'm trying to understand by looking at microsoft.com, but it's hard to find the right stuff there as it is such a big website, there's loads of marketingspeak, and most of the actually useful info is for the old version of Visual Studio, 2003, and I'm using 2005 standard edition. Also note that I'm mostly interested in development of applications, but I would also have to be able to install them for it really being usable. :)

I would get devices with Windows CE preinstalled. Most of the tutorials mention a program named "Platform Builder", is that really necessary for application development only? Also many of the 2003 tutorials mention that there is a Windows CE emulator in Visual Studio 2005, but it seems to have been cut (there are PocketPC emulation included though). I am also missing the "CAB Build" option that is described in the VS 2003 tutorials... Basically, any feedback would be greatly appreciated! 62.119.184.141 13:16, 23 January 2006 (UTC)[reply]

I have VS.NET 2005 Professional and that comes with development tools for Pocket PC, as well as an emulator, but I'm not sure about Standard. enochlau (talk) 13:25, 23 January 2006 (UTC)[reply]

A bit of clarification: there are to some extent tools included, but I'm not sure if it's the complete needed set. However, many of the tutorials mention Platform Builder as well. Also, they mention features of VS 2003 that I just can't find in 2005... Unfortunately I don't have very much experience with Windows CE (otherwise I would hardly be asking...). 62.119.184.141 13:41, 23 January 2006 (UTC)[reply]

Have you tried downloading the Windows Mobile SDK? —David Wahler (talk) 21:38, 23 January 2006 (UTC)[reply]

No, I haven't, but I'll give it a try. But it also specifically says it's for PocketPC - and I'm in the industrial automation business, and will be using industrial PCs running Windows CE... 62.119.184.141 10:03, 24 January 2006 (UTC)[reply]

TINNITUS

HELP! i'm getting desperate. does anyone have a solution to this diagnosis.

i have had a ct, mri, abr, audiology, medication, antihistimines, with little success. all tests were negative. the sound has become so severe that it wakes me up at night and i have three distinct sound levels at the same time: hissing, ringing and bells. all sounds are different frequencies.

hearing aides for white noise did not help. tomos and panorex showed no symptomology,and i had never been exposed to loud noise so that rules out structural deviation.

so what do i do? i'm becoming very frustrated and agitated due to the constant noise.

jackie.

Well, I'm no medical doctor, but I've heard that some people have had tinnitus caused by jaw problems, and some have been able to gain relief through jaw adjustment, exercises and/or muscle relaxants on the jaw muscle. --BluePlatypus 15:09, 23 January 2006 (UTC)[reply]

Yes, the temporomandibular joint causes a lot of problems. I think it's one of the worst designed joints of the human body, along with the knee. —Keenan Pepper 15:25, 23 January 2006 (UTC)[reply]

If it is a TMJ problem, you have two options: Go spend a lot of money with a doctor to get a prescribed mouthpiece to wear at night - or - go buy a standard mouthpiece from any sports store that can be fitted (usually by putting it hot water and then biting down on it). TMJ problems are commonly caused by tension at night. The mouthpiece will keep you from being able to bite all the way down, which forces the TMJ to relax.

However, I'd also look at ear infections as a source. I came back from Norway with a nasty ringing in my ears. After a few months, I used some eardrops for an ear infection and it went away. --Kainaw ^(talk) 16:52, 23 January 2006 (UTC)[reply]

Make sure you aren't taking any meds which contain aspirin, although your problems sound beyond those typically caused by that. Also check all the other meds you regularly take (including birth control) for any mention of tinnitus as a side effect. You might also want to look each up on the internet as it may still cause tinnitus and just not have it listed.

You didn't say whether it's in both ears or one. If just one, I would think that would indicate a problem with the ear itself or the immediate surroundings, such as a partially blocked eustachian tube. StuRat 16:05, 23 January 2006 (UTC)[reply]

I Thank everyone for their answers. all avenues will be investigated. the ringing is bilateral, tomos and panorex (xrays) of the jaw ruled out tmj. will persue it though.

My user page

On my user page I have the babel box and a map of where I live. I want both to be the same size and they are in Firefox, but not in Internet Explorer. Why is this and how do I fix it? Thanks, Gerard Foley 15:01, 23 January 2006 (UTC)[reply]

Why doesn't this suprise me? Probably due to IE trying to change the size of the divs (when it shouldn't be allowed to) - Make sure all layers are given an exact width/height e.g 100px (and don't use IE!) -Benbread 16:38, 23 January 2006 (UTC)[reply]

Yeah, but a problem is many others do use IE. In this case you could just say "fuck 'm", but if you are really serious about getting a page right (ie for a business) you have to make it works at least for the most used browsers. Which, alas, includes IE. DirkvdM 19:33, 24 January 2006 (UTC)[reply]

You can't really blame IE for having annoying features like that. They're mostly remnants from a time when people didn't bother with formatting as much, and it was up to the browsers standard to handle a lot of the values by default. Doesn't mean we should just ignore them though. freshgavin TALK 04:33, 25 January 2006 (UTC)[reply]

If only Microsoft would have adhered to the standards, that would have made life a lot simpler for the standard-makers, who were forced to decide if they should include a fait-accompli. Luckily this didn't happen for the stupid <blink>blink-tag</blink>. That said, Netscape did similar things. Only later browsers like Mozilla (and Opera too, I believe) stuck to the standards. DirkvdM 13:36, 25 January 2006 (UTC)[reply]

Yes IE is crap, but does anyone know what I can do about my user page? Gerard Foley 18:40, 25 January 2006 (UTC)[reply]

The 7 Seas.

Could you please tell me the names of the seven different seas.(bodies of water). Thank You.Nlljj5 at aol dot com 15:15, 23 January 2006 (UTC)[reply]

See Seven Seas. —Keenan Pepper 15:28, 23 January 2006 (UTC)[reply]

Research against the einstein's theory

i remember my friends some months back discussing about a BBC program in which theyintervewed a professor from prbably a US university, who along with other students was researching to prove einstein's theory wrong. all i remember is that he discussed something about orange particles which can travel faster than the speed of light. i searched on wikipedia but dint get a clue. F1 F1 [help help ;)] --Muhammad Hamza 15:41, 23 January 2006 (UTC)[reply]

To which theory are you referring, the General Theory of Relativity, the Special Theory of Relativity, or something else ? Most of Einstein's theories are well proven by now, such as the impressive visual proof of E = mc^2 in an atomic bomb. StuRat 17:28, 23 January 2006 (UTC)[reply]

Eh, there are a lot more subtle verifications of General Relativity than that. For example the Global Positioning System adjusts for time-dialation to due the earth's gravitation, and it works rather nicely. There is no serious research working on proving that Relativity is wrong, although there is of course research in extending it. -- SCZenz 17:37, 23 January 2006 (UTC)[reply]

What, a mushroom cloud isn't subtle enough for you ? LOL StuRat 17:29, 25 January 2006 (UTC)[reply]

It appears the questioner is asking if anyone has proven that something can travel faster than the speed of light. See the "faster than light" section is Speed of light. --Kainaw ^(talk) 17:44, 23 January 2006 (UTC)[reply]

Tachyons are hypothetical particles that travel faster than light; they are not known to exist however. Nor do they contradict Einstein, however they may be impossible for other reasons. For Relativity see Tests of general relativity for conventional point of view. For Anti-Einstein point of view, there are many websites claimning such. eg Autodynamics, aetherometry.com, many others, just google around. GangofOne 01:47, 25 January 2006 (UTC)[reply]

Health hazards of laptops

Is there any study that points out health hazards of keeping a laptop on the top of yourself while working day after day? deeptrivia (talk) 17:10, 23 January 2006 (UTC)[reply]

The low power level and LCD display seem to make EM radiation much less of an issue than with a desktop PC. I would think the most likely injury would be from bending over to use it or carpal tunnel syndrome from the keyboard. StuRat 17:24, 23 January 2006 (UTC)[reply]

There have also been a few documented cases of minor burns from keeping a warm laptop directly on your lap. You're much better off with a tray or table between you and the laptop—for men especially. (Excess heat harms sperm; your testicles hang down away from the body to keep them cool, and the ancient Egyptians sometimes used a hot bath before sex for birth control.) TenOfAllTrades(talk) 17:39, 23 January 2006 (UTC)[reply]

Yes, but none of us want User:deeptrivia to reproduce anyway. LOL. J/K. StuRat 20:16, 23 January 2006 (UTC)[reply]

Haha..LOL! deeptrivia (talk) 21:44, 23 January 2006 (UTC)[reply]

BBC News: Laptops May Damage Male Fertility [8] --JianLi 01:09, 25 January 2006 (UTC)[reply]

How to find a telephone number

I have a friend in Pittsburgh but I don't know his telephone number or address. I just know his name. How do I find his telephone number? Also, if I have a number, is it possible to find out the name? I don't have access to phone books because I live in India.

You could try Google Phonebook. joturner 19:12, 23 January 2006 (UTC)[reply]

Ball lightning and crop circles

How does ball lightning and crop circles occur?

ball lightning (disputably) occurs due to certain atmospheric conditions. crop circles occur due to people with planks of wood, string, creativity and a lot of time on their hands going out into fields at night. --Noodhoog 19:29, 23 January 2006 (UTC)[reply]

I suppose whirlwinds could also be the culprit in some crop circles. StuRat 20:02, 23 January 2006 (UTC)[reply]

well i saw a video on Discovery channel that showed an actual crop circle that formaed when a ball of light passed over it n the night --84.11.108.4 17:03, 24 January 2006 (UTC)[reply]

The drunk farmer with the plank had a mining helmet on when he made it. freshgavin TALK 04:36, 25 January 2006 (UTC)[reply]

animal sexuality

Are there homosexuals among animals? If not, why?

Offhand, I know that Bonobos will have sex with anything that moves, and most things that don't. I also seem to recall that someone won an IgNobel prize a few years back for documenting a case of homosexual necrophilia in the mallard. I'm sure there are plenty of other cases. GeeJo _{(t) (c)} • 19:30, 23 January 2006 (UTC)[reply]

[9] —Ilmari Karonen (talk) 15:22, 24 January 2006 (UTC)[reply]

This article states that "birds, reptiles, mammals and even snails engage in same-sex sexual activities." - Akamad 19:37, 23 January 2006 (UTC)[reply]

Wikipedia has always seemed to have a penchant for attracting people who like to make lists of things, regardless of if they're useful or not. I'll leave that up to you to decide. Without further ado, I present you with: List of animals practicing homosexual behavior. --BluePlatypus 20:33, 23 January 2006 (UTC)[reply]

That's hilarious. It belongs on WP:UA :) GeeJo _{(t) (c)} • 21:49, 23 January 2006 (UTC)[reply]

And now it's there! GeeJo _{(t) (c)} • 21:51, 23 January 2006 (UTC)[reply]

There was (still is?) a famous pair of geese at a zoo (in Canada, IIRC) which were nicknamed Gertrude and Alice (after Stein and Toklas) by their keepers when it became obvious they, um, weren't interested in ganders. Grutness...wha? 22:56, 23 January 2006 (UTC)[reply]

Also, there is the case of the gay penguins. --Robert Merkel 23:57, 23 January 2006 (UTC)[reply]

A good documentary on the subject is Dr Tatiana's Sex Guide to All Creation, based on the book by evolutionary biologist Olivia Judson.--nixie 02:43, 24 January 2006 (UTC)[reply]

That 'List of animals practicing homosexual behavior' even features the 'queen butterfly'. Cute! DirkvdM 19:40, 24 January 2006 (UTC)[reply]

Ehm , that requires a litte more explaining. The Spanish word for 'butterfly', 'mariposa', has the same meaning as 'queen' in English in this sense. DirkvdM 19:45, 24 January 2006 (UTC)[reply]

Hmm, in French butterfly is "pappillon", in German it's "schmetterling", in Dutch it's "vlinder", in Portuguese it's "borboleta". It seems odd that it apparently has a completely unrelated word origin in all those languages. StuRat 07:15, 25 January 2006 (UTC)[reply]

One species that I found interesting was the Desert Grassland Whiptail lizard. The species is comprised solely of females, but they practice mating rituals to enhance ovulation. Dimblethum 23:53, 25 January 2006 (UTC)[reply]

Earth's magnetic poles

Why do the polarities of earth's magnetic field reverse?

See Geomagnetic reversal :) GeeJo _{(t) (c)} • 19:34, 23 January 2006 (UTC)[reply]

You're all robots!

Is there a specific name for the condition of being under the belief that your friends, family, or other specific people are impostors (actors, clones, robots, pod-people, or similar) who are either keeping the real ones somewhere or have killed them? I checked the pages on paranoia, schizophrenia and delusions, and even invasion of the body snatchers, but couldn't find any mention of this particular condition. --Noodhoog 19:25, 23 January 2006 (UTC)[reply]

See Capgras delusion :) GeeJo _{(t) (c)} • 19:32, 23 January 2006 (UTC)[reply]

Beep! --GraemeL ^(talk) 19:35, 23 January 2006 (UTC)[reply]

Ha! I knew it! No human could have answered so quickly. Thankyou, oh wikipedian artificial hive-mind. --Noodhoog 19:39, 23 January 2006 (UTC)[reply]

You must be mistaken. There is no Hive Mind! GeeJo _{(t) (c)} • 19:44, 23 January 2006 (UTC)[reply]

That's what the cabal wants you to think! Cernen Xanthine Katrena 07:21, 24 January 2006 (UTC)[reply]

I'm a dolphin, not a robot. — Knowledge Seeker দ 07:23, 24 January 2006 (UTC)[reply]

Gah!! Just as I pulled up this section to read it, the intro to "One Note Song" by Tenacious D [10] started playing in WinAmp. Totally freaked out right now... --P e ruvianLlama^(spit) 17:57, 24 January 2006 (UTC)[reply]

salman rushdie

What was the subject matter of Salman Rushdie's controversial novel The Satanic Verses?

Try looking under, oh, I don't know, The Satanic Verses maybe ? StuRat 19:52, 23 January 2006 (UTC)[reply]

When asked about his unusual first name, Salman replied "My father was an avid fisherman. Still, I fared better than my sister Bigmouth and my brother Crappie." LOL. StuRat 19:55, 23 January 2006 (UTC)[reply]

Is his name actually pronounced as the fish? I've heard his name said before (in Canada) and I've always thought it was Sahl-man Rush-dee. freshgavin TALK 05:24, 24 January 2006 (UTC)[reply]

That's true. StuRat 07:03, 24 January 2006 (UTC)[reply]

Then I guess ... lucky for him : ). freshgavin TALK 07:08, 24 January 2006 (UTC)[reply]

Perhaps the joke would work better if we were talking about Salmon P. Chase, whose name is at least spelled the same as the fish. I believe the L is pronounced there, too. Only the fish seems to have a silent L. But then, how many other words have a silent L ? StuRat 07:03, 24 January 2006 (UTC)[reply]

"Palm", depending on how you pronounce it (I pronounce the L, but many don't). Ian Holm? Folk/yolk/talk/walk? That's all I can think of offhand. — Knowledge Seeker দ 07:32, 24 January 2006 (UTC)[reply]

Balm, calm, qualm, realm (oops!). And of course the second 'l' in words like 'ball'. DirkvdM 19:54, 24 January 2006 (UTC)[reply]

You could argue that the L exists in influencing the pronounciation. I certainly don't think of cam when I say calm. The strength of the L sound depends on your accent though. By the way realm isn't included in this, the L is quite pronounced. freshgavin TALK 04:42, 25 January 2006 (UTC)[reply]

Which is why I said 'oops'. Might have added a smiley. So here it is. :) DirkvdM 13:44, 25 January 2006 (UTC)[reply]

I pronounce the L in palm, balm, calm, qualm and realm. In all of those other words, it does affect the pronounciation..."foke", "yoke", "tawk", "wawk". StuRat 06:44, 25 January 2006 (UTC)[reply]

Sure it affects the pronunciation, but letters don't have to be sounded to affect pronunciation. "Hat" and "hate" are pronounced differently, although the e is silent. The l is still silent in "yolk" and "talk". There will be numerous examples of letters affecting pronunciation even if they are not making their usual sound due to English's sometimes bizarre and chaotic pronunciation patterns. — Knowledge Seeker দ 06:55, 25 January 2006 (UTC)[reply]

I think "yolk" is perhaps the most convincing of these - I've never heard an accent where that 'l' was audible, unlike "folk", "talk", etc, which have quite varied pronunciation. However, it was presumably pronounced once to have been standardised to that spelling, unless it was by erroneous connection to something else... - IMSoP 16:16, 26 January 2006 (UTC)[reply]

Salman is a Muslim name and its pronounced Sull(like dull) - maaan(the a is pronounced like in yarn)

Unencrypted Network Connection

When confirming an e-commerce transaction my browser presented a message stating the data would be sent over an unencrypted network connection. The lock symbol was visible on the right hand side of the bottom bar in XP.

What does the message really indicate about the security of the transaction? Is there anything I must do or this a security problem at the vendor's end?

Gloria

--64.220.183.164 21:27, 23 January 2006 (UTC)[reply]

The page you were viewing might have been using SSL, but that does not guarantee all communications with the host are secure. If your browser warned you it might be insecure, then it probably is. Your best course of action would be to hold off completing the transaction until you get a response from the other party about the security of the link. Tzarius 22:32, 23 January 2006 (UTC)[reply]

Sometimes the confusion results from an html page which otherwise uses the https protocol, but has a form on it which is not SSL. (There are also examples of the opposite-- an unencrypted page that has a secure form with an method such as post https:...) If you examine the page properties (most browsers will allow this), it will list the properties of the form. If the form action is to post using http rather than https, the browser will issue an alert because form is not secure and should not be used.--Mark Bornfeld DDS 23:26, 23 January 2006 (UTC)[reply]

"pod" means what?

What does "pod" as in "ipod" or "pod casting" stand for?

As far as I'm aware it's not actually an acronym, just a name that Apple's marketing division thought up. Interestingly, however, since the term "podcasting" came into common use for scheduled audio downloads from the web, the Creative company (who also manufacture MP3 players) have tried to redefine it as standing for "Personal On Demand cast". However, the term originally came from the act of downloading these shows to an iPod. Finally, I can't help but mention I consider "podcast" to be the worst term the 'net has spewed out since "information superhighway". --Noodhoog 23:09, 23 January 2006 (UTC)[reply]

pod --Zeizmic 01:00, 24 January 2006 (UTC)[reply]

The applicable "pod" definition from www.m-w.com is: "a usually protective container or housing", as in a protective container for music, in this case. By contrast, a CD is music in a non-protective container. This is why CDs must be put inside a CD case, to prevent scratches, etc., which might ruin the music. An iPod is a bit more durable than that. StuRat 06:56, 24 January 2006 (UTC)[reply]

Before the Big Bang

I've heard that time and space didn't exist before the Big Bang.I've also heard that, before the Big Bang, there was an infinitely dense point of matter called a singularity.But then, how can there be a singularity(or anything) before the Big Bang if time didn't exist?I've heard that the Big Bang was caused by quantum fluctuations.But without space and time, how can there be quantum fluctuations or any other physical processes?

Media:User:Bowei

I'm certainly no physicist, but a while back I heard an interesting analogy regarding time before the big bang. Imagine you started travelling south, eventually you would hit the south pole. Then what happens if you try to go south from there? You can't. It's not that there's a wall in your way or anything like that, simply that there is no such thing as south from there, it doesn't exist. Apparently that's vaguely similar to how it is with time and the big bang - time before the big bang doesn't exist. Again, however, I will stress this is just "an interesting analogy that I heard once", and I'm not even remotely qualified to say whether it's meaningful, or just utter tripe. --Noodhoog 23:18, 23 January 2006 (UTC)[reply]

Well, the singularity was at the big bang. At point zero so to speak, not before it. I don't think the BB was caused by quantum fluctuations though. Noone knows exactly what happened then since the current model of physics really breaks down completely. --BluePlatypus 23:53, 23 January 2006 (UTC)[reply]

Testicular pain

Testicular pain currently redirects to orchitis, although web search indicates that this is only one possible cause. There is no article testicle pain. Anyway, my question is whether a week of mild testicular pain in the absence of any other symptom (no abdominal pain, no fever, no discharge, no recent trauma, et cetera) is reason to see a physician. Thanks. 128.220.220.95 23:18, 23 January 2006 (UTC)[reply]

That's the sort of question we can't answer, because we're not physicians. You could perhaps call your physician's office and ask them...? -- SCZenz 01:04, 24 January 2006 (UTC)[reply]

And those of us who might be physicians agree with that advice. Testicular pain for a week isnt a sore throat and there isnt a common, "oh it's probably just XX, and it will be better in a couple of days." Make an appt for a few days from now and try some ibuprofen for 2 days and then stop, and the response to the ibuprofen will be a useful piece of information that will not screw up any of the diagnostic issues. If it is severely painful or swollen go directly to the ER. alteripse 02:31, 24 January 2006 (UTC)[reply]

Thank you very much. This is very helpful. 128.220.220.95 16:17, 24 January 2006 (UTC)[reply]

It's amazing... Wikipedia has all kinds of people, including physicians! But should we really be dispensing this kind of advice here? It might discourage people from visiting the doctor in real life. enochlau (talk) 06:20, 24 January 2006 (UTC)[reply]

We could create Wikipedia:Reference desk/Medical_emergency and people could ask questions like, "omg my armz r bleding wut do i do lolz," or "Help my hair is on fire, will that turn its mass into energy?" Cernen Xanthine

Katrena 07:38, 24 January 2006 (UTC)[reply]

Most physicians are very careful about dispensing medical advice over the internet or phone. I'm sure a Wikepedia medical reference desk would be swamped by people (proabably uninsured Americans) looking for free medical advice. Cybergoth 22:37, 24 January 2006 (UTC)[reply]

Sounds like you're going to the doctor, so good for you. If your tests don't turn up anything, try wearing a jockstrap when you exercise. — BrianSmithson 19:34, 24 January 2006 (UTC)[reply]

Black holes and energy-to-matter conversion

Hello. Two physics questions:

If nothing ever comes out of black holes, will everything eventually be sucked inside them?
I can think of many ways of transforming matter to energy, from fire to matter-antimatter annihilation. Yet I can't think of one way to convert energy to matter. Can someone give me some example?

Thanks! -- ironcito 23:47, 23 January 2006 (UTC)[reply]

No, I don't think everything will be sucked inside eventually. First, there's light, nothing moves faster than light in vacuum, including gravity, so light headed away from a black hole will never be 'sucked in'. Second, black holes are just like any other gravitational object: You can fall into a stable orbit around it, just like with a planet or sun. Of course, most black holes are spinning and have so much junk in their orbits that they form Accretion disks, where the stuff in orbit collides and slows down and eventually falls in. Also, things do get out of black holes, namely Hawking radiation, so the survival question is really if the black hole will be able to suck things in faster than the Hawking radiation is emitted or vice-versa. As for question 2, that's what high-energy particle accelerators are for. (BTW, fire doesn't turn matter into energy, you have the same amount of matter before and after) --BluePlatypus 00:09, 24 January 2006 (UTC)[reply]

Agreed. Fire does not convert mass into energy. If you added up the weight of the ashes and gases created, they would exactly equal the starting materials. This common misperception is due to only weighing the ashes. If the weight of the gases had been converted into energy, the resulting explosion would be around 10,000 times the detonation energy of a nuclear weapon with the same mass of fissible material and would likely rupture the Earth's crust. In a fire the energy in chemical bonds is changed into free energy. StuRat 06:42, 24 January 2006 (UTC)[reply]

Um, no. Fire does convert matter to energy, just not very much. E = mc² holds for all reactions, not just nuclear reactions. However, in all but nuclear reactions, the energies involved are small enough that the c² term dominates, resulting in a mass change so tiny as to be immeasureable and, in efffect, negligible. (c² is of course a really big number.)

If you made a little fire that released 1 kcal of energy (enough to heat 1 liter of water 1 degree Centigrade), and if you weighed the ashes and all the soot and CO₂ and all the other products afterwards, you'd find that they were lighter by something like 4.7 x 10^-11 grams, or 47 picograms. But you wouldn't really "find" this, because it's much too small to measure; it's about a million times lighter than the best analytical balance can weigh.

But since E = mc² everywhere, it means it's just as easy for any of us to convert energy back into mass -- again, just not very much of it. For example, if I do some work which involves applying a force of one pound over a distance of one foot, I will have expended about 1.4 Joules of energy. If the work involves compressing a spring, and if we could weigh it accurately enough afterwards, we would find that because of the stored energy it was 1.5 x 10^-14 grams heavier, or 15 femtograms.

Steve Summit (talk) 16:36, 24 January 2006 (UTC) [Disclaimer: I'm not a physicist; some of my numbers here might be wrong.][reply]

What? No. Fire does not involve the release of elementary particles from atoms, it's just an exothermic chemical reaction that typically involves oxygen. And potential energy (such as the compressed spring) does not add mass. Heat does not add mass (until you get the individual particles moving relatavistically). Relatavistic motion adds mass. Tzarius 22:26, 24 January 2006 (UTC)[reply]

Steve Summit is right. E=mc^2 applies to all reactions, including chemical rxn like combustion. Fire releases heat, which is kinetic energy and photons. Photons are particles which is the "release of elementary particles from atoms" if you want to think of it that way. In combustion, binding energy is broken , then reformed, just less than was broken; it's just chemical binding energy. In a nuclear rxn. it's nuclear binding energy, but the concept is the same. A compressed spring is more massive than an uncompressed spring. If I have enough to equal the energy release of a nuclear explosio, and I explode them, then the springs have the mass of the uncompressed springs, then were did all the energy come from? The uranium nucleus is alot like a compressed spring. Relativistic motion or not has nothing to do with it. (By the way, relativity is true at all speeds. It's just too small to measure at low speeds.) If you don't believe what I say, than ask around , or argue. Maybe your teachers are lying to you. GangofOne 01:33, 25 January 2006 (UTC)[reply]

Thanks fer stickin up fer me there, Gango. :-) Tzarius, there's a very nice explanation of what I'm talking about in the excellent book The Ring of Truth, by the late Philip Morrison, written as a companion to the PBS television series of the same name. So far, the only source I've found on the web is http://www.newton.dep.anl.gov/askasci/chem03/chem03534.htm, which says that people like me are being "cute" in our arguments (a charge which I'll have to cop to), but we're not wrong. Basically, nowhere is it written that E = mc² applies only to nuclear reactions, or only to reactions in which entire elementary particles are created or destroyed -- it applies to all reactions. And when you've got potential energy stored in a system, how do you know it's there? It's not there just because you say it is. In effect, the way the universe keeps track of it -- "remembers" that it's there, if you will -- is by recording it as actual mass. Steve Summit (talk) 02:22, 25 January 2006 (UTC)[reply]

No again. Chemical reactions do not convert ANY mass to energy. For example, the combustion of oxygen and hydrogen to make water (and release energy) looks like this:

2H₂ + O₂ -> 2H₂O

There are the same number of atoms on both sides of the equation, and each has the same number of protons, nuetrons, and electrons (and thus the same total mass). The energy is released since the reactants have a higher energy state in their chemical bonds than the resulting water.

In the case of the compression or expansion of a spring, or any elastic material for that matter, the energy released was potential energy in stretched or compressed chemical bonds. These bonds are formed with electrons. In the conventional model these were described as spheres in orbit about the nucleus. The orbits can temporarily be forced inward or outward by application of a force, but will "want" to reestablish the original orbital distance once the force is removed. This same effect can be seen in satellites we put in orbit around the Earth. If we try to move them to a higher or lower orbit without changing their orbital speed they just return to the stable orbit for that speed. Current quantum mechnics theory of electrons is far more complex than the simple model I used here, but basically arrives at the same result. StuRat 06:29, 25 January 2006 (UTC)[reply]

Ok, I read that link, and this ("an electric field has mass which will seem to be stuck to the object holding the charges that originated it.") made sense in that odd kind of way. But then I got down to Roberto Gregorius' reply, and he knocks it all down again. (I also read Binding energy, and that makes sense to me). So I want to make another couple of examples: First one is two gasses, one at low pressure/large volume and the other at high pressure/small volume (both same Mole count). The compressed gas obviously has more energy to do work (in a vacuum), but I don't see how crowding atoms loosely together will add to the mass-energy.

The second example is a magnet, in two time-seperated states - non-magnetised, and magnetised. Non-magnetised, the magnetic domains are not uniformly arranged, whereas in the magnetised state most of them point in a single direction. The magnetised metal has more potential energy, but how does the orientation of the domains increase their mass?

Sorry if I'm missing something completely obvious, but I just don't see the relationship... Tzarius 06:09, 25 January 2006 (UTC)[reply]

There is nothing to be sorry about. You are entirely correct that no mass is converted to energy in ordinary chemical or physical reactions. StuRat 06:34, 25 January 2006 (UTC)[reply]

Oh joyous day, a day when one can learn something new. This came up before, at Wikipedia:Reference_desk_archive/Science/January_2006#inventing_a_source_of_perpetual_energy. I looked at the link above from www.newton.dep.anl.gov, a site for K-12 educators, and they , overall, have a jumble of misunderstandings, so it's no surprize that the jumble of misunderstandings is passed on to the new generation. You say 2H₂ + O₂ -> 2H₂O has the same number of protons, neutrons and electrons on each side of the eqn. Let's look at a typical fission rxn n + 235U -> 141Ba + 92Kr + 3n. In this case also there are the same number of protons, neutrons, and electrons, yet energy is released E=mc^2, and that m is the mass defect of products minus reactants..... So, what about the chemical rxn? I say the same applies. THere is a "mass defect" in the products. How so? Have we actually accounted for all the particles? What about the "particles of exchange" in the binding energy, aka the "gauge bosons", that is the source of the binding energy? If I compress a spring, I force atoms closer. There are more exchange photons, more energy, more mass. More later GangofOne 20:04, 25 January 2006 (UTC)[reply]

But a nuclear reaction also releases non-virtual photons as a result of the loss of binding energy... Tzarius 01:21, 26 January 2006 (UTC)[reply]

True, but I not sure what point you're making. In both a chemical rxn and nuclear rxn the resultant particles' kinetic energy and the energy of released photons, together divided by c^2, gives the "mass defect" of the rxn. GangofOne 00:30, 27 January 2006 (UTC)[reply]

Interesting! Obviously thought-experiment is not enough to come to a conclusion, we must seek out experimental evidence! By chance, is there some kind of short phrase or keyword that sums up this whole business? Tzarius 23:37, 27 January 2006 (UTC)[reply]

Part 1: no, for two reasons. firstly, astronomers currently believe the universe is accelerating its expansion, so matter cannot all fall into a single black hole. Secondly, Hawking radiation comes out of black holes. Part 2, particle-antiparticle pair creation is the standard example (which incidentally is the cause of Hawking radiation) Modest Genius 00:14, 24 January 2006 (UTC)[reply]

January 24

Pluto

I read somewhere that if the ship for Pluto was not started before like the 4th of February, it wouldnt be able to launch for another five years. Why is that? Thanks Zach 01:05, 24 January 2006 (UTC)[reply]

The plan is to get a boost from Jupiter, see New Horizons. --JWSchmidt 02:10, 24 January 2006 (UTC)[reply]

For "boost", see gravitational slingshot. The reason is simply that, as the planets move, after February 14 the probe would not have enough fuel to reach Jupiter on an alignment that would enable it to reach Pluto afterwards. --Anonymous, 04:35 UTC, January 24.

I don't think what you read was correct:

According to our New Horizons article right before the launch, it could have launched after February 4, but it would not have been able to get a gravity assist (or as good of a gravity assist), so it would have to arrive years later. If it missed the 2006 window completely, there would have been another launch window in 2007. --AySz88^-^ 06:31, 24 January 2006 (UTC)[reply]

Got it Thanks, I didnt understand but now I do!!! Zach 00:11, 25 January 2006 (UTC)[reply]

You're welcome, and thank you! Enjoy Wikipedia! --AySz88 ^-^ 03:13, 25 January 2006 (UTC)[reply]

Hurricanes and Typhoons

In 1900, a hurricane struck the Texan town of Galveston.Well, Houston is very close to Galveston.So how much was Houston affected by the Galveston Hurricane of 1900?

Note that the large number of deaths in Galveston was because they built homes on a sandbar. Building homes on a sandbar in "hurricane alley" is beyond stupid. StuRat 06:31, 24 January 2006 (UTC)[reply]

And how much was Houston affected by Hurricane Rita?

Why is 119km/hr considered the minimum wind speed for a hurricane?

How often on average do North Atlantic hurricanes occur?How often do typhoons occur?

I've heard that typhoons are usually much stronger than Atlantic hurricanes.Is that true?

When was the last time a typhoon struck the following places:Hong Kong,Shanghai,Osaka,Tokyo?

The damage to Galveston was mainly from the storm surge, and storm surges do not travel very far inland. Galveston was the larger city at the time, so it had more buildings to be damaged and more people to be killed.
Not very much. See Hurricane Rita.
That's where Saffir and Simpson set it. Why, I'm not sure; possibly because it's the point at which such storms start to do widespread damage.
See Tropical cyclone#Locations of formation, which has some data on this.
The largest and strongest tropical cyclones on record were NW Pacific typhoons, but I don't know if, on average, they're any stronger.
Typhoon York hit Hong Kong in 1999, Typhoon Matsa hit Shanghai in 2005, Typhoon Tokage hit Osaka in 2004, and Typhoon Mawar grazed Tokyo in 2005.

—Charles P. (Mirv) 02:23, 24 January 2006 (UTC)[reply]

On question 3, the threshold originally comes from when the Beaufort Scale began to be interpreted in terms of specific wind speeds: see that article. (I'm not sure if the numbers given there article are exactly right, though; most sources show the minimum speed for a hurricane slightly higher. Unfortunately, because the speeds are typically rounded to whole numbers in any of three different units, errors are often introduced when the table is copied.) --Anonymous, 04:40 UTC, January 24.

Two points, living in Tokyo I usually hear that hurricanes are considered stronger than typhoons, and though I haven't seen any figures I'd like to agree with that. There are usually close to 20 (named) typhoons in the typhoon season every year, and in fact quite a few of them hit Tokyo and Osaka (there is a fair chance that it could hit both cities). Tokyo was hit/grazed/passed over at least 2 times last season (fall, 2005) but it depends on what you mean by 'hit'. I don't believe there was any major damage in south East Japan this year, maybe some minor flood damage. freshgavin TALK 05:14, 24 January 2006 (UTC)[reply]

Powerful typhoons occur far more frequently than Atlantic hurricanes of the same strength. Take a look at List of notable tropical cyclones#Most intense storms on record, where we had to stop listing the typhoons to give some hurricanes from other basins a chance to be represented in relative strength. The top 13 tropical cyclones are all typhoons, and an Atlantic hurricane doesn't appear until number 19 (Wilma).

I'm fairly certain that 2005 is the first year on record when there was more Atlantic named storms than Pacific named storms. On average, there are 11.8 named storms (5.9 hurricanes) a year in the Atlantic, compared with 31.8 storms (17.5 typhoons) a year in the Pacific. (from a table on Dr. Master's blog)

Make sure you don't confuse between Pacific hurricanes (generally, nearer to Mexico) and Pacific typhoons (near Asia). --AySz88^-^ 06:44, 24 January 2006 (UTC)[reply]

Freshgavin: I'm very surprised that people in Japan think hurricanes are stronger. Perhaps you're better-prepared, so our hurricanes do more damage? --AySz88^-^ 06:49, 24 January 2006 (UTC)[reply]

I merely said that I often hear that hurricanes are more powerful, the opinion of the average Tokyo citizen is thus. Presumably because of the way the media presents hurricanes in Japan. Then again, many Tokyo citizens will tell you that Hawaii is bigger than the Japan! I have no opinion; I'm from Toronto and have never experienced a hurricane before. It may be that the Japanese are better prepared ... at least in terms of emergency response. freshgavin TALK 07:07, 24 January 2006 (UTC)[reply]

I guess we Americans aren't the only ones who are bad at geography. StuRat 21:17, 24 January 2006 (UTC)[reply]

Love-causing Hormones (cont.)

I know that the the beautiful a woman is, the more likely other men will fall in love with her.But what if the 3 women the man meets are equally beautiful?

Well everyone has personal tastes. One of the women might be more to the man's liking - a brunette instead of a blonde. But if they're triplets - to continue the hypothetical - or even if not but they are all judged equally attractive by the man, other factors will come into play: personality, level of interest they express to him, and so on.

Of course, this doesn't tell all that much about hormones and love. Yes there's an element of the psychological - the personal taste, which is likely in part psychological - but hormones (or more properly our long genetic inheritance) also plays a major role in what personality traits we find attractive. There's just no sensible way to absolutely disentangle the physical and the psychological here. (Of course, the two aren't that different anywa, but I digress.) Humans are more complicated than that. --George 01:56, 24 January 2006 (UTC)[reply]

It's whichever one has the shortest skirt. Fact. Proto t c 11:00, 24 January 2006 (UTC)[reply]

But don't ignore Jimmy Soul's take on this topic. --Shantavira 13:03, 24 January 2006 (UTC)[reply]

Hurricanes & Typhoons (cont.)

Imagine if a hurricane struck New York City!Well, how likely is it that a hurricane will strike New York?Is New York in place where it's likely to be hit by a hurricane?

When was the last time a typhoon struck Beijing and Tianjing?

A hurricane did strike New York City in 1893. Two more (in 1938 and in 1944) just missed it. So no, New York City is not likely to be struck by a hurricane, but it certainly could be. —Charles P. (Mirv) 02:29, 24 January 2006 (UTC)[reply]

New York is struck by hurricane remnants much more often, but actual hurricane strength winds and storm surge are rare, as hurricanes typically reduce in strength as they head that far north. A large amount of rain is typically all they get in NY from a hurricane. StuRat 06:25, 24 January 2006 (UTC)[reply]

I'm reminded of a Lewis Black quote (I'll paraphrase): "They [The Weather Channel] said that [Hurricane Floyd] was headed for the east coast and that it would hit somewhere between Miami and New England. Why the f*ck open your mouth? Why not just say 'Hey, Hurricane Floyd's coming and, uh...we're going to go to commercial.'" Cernen Xanthine Katrena 07:42, 24 January 2006 (UTC)[reply]

pulmonary parenchyma

Hi,

I would just like to know what pulmonary parenchyma is in regards to community aquired pneumonia. I know CAP is an acute infection of the pulmonary parenchyma.

Thanks

Amit

Pulmonary parenchyma is what we call lung tissue when you pay us $250. alteripse 03:39, 24 January 2006 (UTC)[reply]

or $127.50 CDN in Ontario. Cybergoth 22:40, 24 January 2006 (UTC)[reply]

I think your conversion is backwards. Canadian dollars are worth less than US dollars, so you would need more of them to equal the same amount, not fewer of them. StuRat 17:05, 25 January 2006 (UTC)[reply]

You missed the point - Canadian physicians are paid much less than physicians in the USA. Cybergoth 01:31, 26 January 2006 (UTC)[reply]

Ok, I get it now. StuRat 05:22, 26 January 2006 (UTC)[reply]

windows server 2003

What are the driver signing options in 2003 server?

~~A rather unclear question, that; however, I offer you Microsoft Windows 2003, Driver signing, and Drivers. Cernen Xanthine Katrena 07:24, 24 January 2006 (UTC)~~[reply]

And of course, I r t3h sux0rz, and none of those articles exist. Sorry to be a bother. Cernen Xanthine Katrena 07:44, 24 January 2006 (UTC)[reply]

It's Windows Server 2003. Proto t c 10:58, 24 January 2006 (UTC)[reply]

Brain wave experiments

I remember watching a documentary about the brain a while back that gave some information on an experiment (I believe by 2 amateur scientists) in sharing brainwaves (for the hell of it). I think the experiment was performed in the late 70s or 80s, and it was probably done with the pretext that it might be possible to enduce telepathy by amplifying brain patterns. I don't remember details of the experiment, other than the fact that it may have done with both subjects simultaneously or with recorded brain waves from one subject, and the results were simply that the brain couldn't handle/understand the input and the scientists were rather disturbed by the experience, so they gave up.

It might not have been simply brain waves, now that I think about it. freshgavin TALK 05:37, 24 January 2006 (UTC)[reply]

Lawl, wtf. There's no question here! Cernen Xanthine Katrena 08:17, 24 January 2006 (UTC)[reply]

I think FG is asking for the name of the documentary. Or perhaps for information on Brain waves? GeeJo _{(t) (c)} • 08:34, 24 January 2006 (UTC)[reply]

- Do you know that brainwave frequency increases when we catch the punchline of a joke? ^KILO-_LIMA 18:04, 24 January 2006 (UTC)[reply]

Oops - -; I forgot to actually ask the question. Yes has anyone heard of this experiment or one like it? There is no useful information on this particular train of thought on Brain waves or articles related to it. freshgavin TALK 23:54, 24 January 2006 (UTC)[reply]

Sounds like the fictional movie Brainstorms GangofOne 01:15, 25 January 2006 (UTC)[reply]

It wasn't : (. It was definitely TLC or Discovery Channel. freshgavin TALK 04:48, 25 January 2006 (UTC)[reply]

Bascillus Subtilius

How is bascillus subtilius growth affected by the change of dettol pH.

According to our dettol article, pH has nothing to do with it. The bacteria are killed because they can't handle alcohol. - Mgm|^(talk) 11:31, 24 January 2006 (UTC)[reply]

Also the bacteria you want is spelled Bacillus subtilis. It can cause food poisoning, but I don't think you'll be using dettol in your food!!! - Nunh-huh 03:47, 25 January 2006 (UTC)[reply]

Is it a particularly subtle bacteria ? StuRat 09:03, 27 January 2006 (UTC)[reply]

computer

What is print routine?

You may be interested in computer software whose function includes printing. User:AlMac|^(talk) 13:04, 24 January 2006 (UTC)[reply]

Though it's not a routine, it sounds like you might want to read printf as well. Dismas|^(talk) 23:10, 24 January 2006 (UTC)[reply]

TSR program

What is a TSR program and what are its applications?

Please, see Terminate and Stay Resident. Don't forget to check the Wikipedia before asking for help! Mariano(t/c) 12:34, 24 January 2006 (UTC)[reply]

I'll create TSR program as a re-direct to Terminate and Stay Resident. ike9898 20:44, 24 January 2006 (UTC)[reply]

Alas! TSR already exists to that redirection. We also need Terminate and Stay resident Program, terminate & stay Resident Prog., ... ---DLL 22:59, 24 January 2006 (UTC)[reply]

If the redirects were handled a little bit more efficiently (pseudo redirects and the like) a bot could do that automatically. freshgavin TALK 04:49, 25 January 2006 (UTC)[reply]

Einstein

Can u explain the special and general theory of relativity and the concept of curved space in detail?

We already did! See Special relativity and General relativity. Next time use the search box at the left. ☢ Ҡieff⌇↯ 12:48, 24 January 2006 (UTC)[reply]

Antimatter

What is antimatter and what do you mean by matter-antimatter annihilation and what is a particle generator and is it true that matter was created from nothing?

See antimatter, annihilation and electron-positron annihilation, particle accelerator, particle collider and pair production. ☢ Ҡieff⌇↯ 12:49, 24 January 2006 (UTC)[reply]

And if you can't understand any of that, antimatter is the opposite of matter and if you can find some antimatter and put it in contact with its respective matter than it creates a big fuss called matter-antimatter annihilation. It is not true that matter was created from nothing, and yes, there's a boogyman in your closet, but I'm not going to explain why. freshgavin TALK 04:53, 25 January 2006 (UTC)[reply]

The "big fuss" is that all the mass would change into an immense amount of energy, on the order of 10,000 times more than a nuclear bomb with the same mass of fissible material, since in nuclear bombs only about 1/10,000 of the fissible mass is converted to energy. The amount of energy produced is described by Einstein's

E=mc^{2}

. StuRat 05:44, 25 January 2006 (UTC)[reply]

Which makes one wonder how the Italians get away with serving antipasta .... --Blowdart 13:23, 26 January 2006 (UTC)[reply]

You just have to be careful not to let it ever touch any pasta, LOL. StuRat 09:00, 27 January 2006 (UTC)[reply]

einsteins theory of relativity

could someone please explain to this lay person the quotion E=MC^2 in simplistic terms. i was under the impression it referred to time travel, however, some of the men i work with indicate it refers to time standing still. which is it?

many thanks, jaclyn

It has nothing to do with time travel.

the E means Energy
the M means mass (physical material)
the C means the speed of light
the 2 means C squared
thus if you have a tiny amount of mass, like the inside of a nuclear bomb, the amount of energy released by exploding it is equal to the mass times speed of light twice User:AlMac|^(talk) 13:07, 24 January 2006 (UTC)[reply]
Well, it's not the original mass, but the mass lost in the process (that mass turns into energy). Mariano(t/c) 14:57, 24 January 2006 (UTC)[reply]

Some people are really nice here, and then there's me. You must be in the same class as the person two doors up. The Magic Answer Box is always ready for you. Try it with 'Einstein' and follow the links. It's fun! --Zeizmic 13:11, 24 January 2006 (UTC)[reply]

thank you (almac) for your excellent response. to zeizmic- so i'm scientifically challenged, "TO KNOW WHAT YOU KNOW AND TO KNOW WHAT YOU DON'T KNOW ARE THE CHARACTERISTICS OF ONE WHO KNOWS!

Actually, Zeizmic's response agrees with you. It's akin to the "give a man a fish/teach a man to fish" thing, because "know[ing] what you don't know" (aside from sounding much like Donald Rumsfeld) is fairly useless until you know how to learn what you don't know. To wit, the caps lock key is to your left. — Lomn Talk 15:46, 24 January 2006 (UTC)[reply]

It is not a matter of "knowing". It is a matter of taking responsibility for yourself. Zeizmic simply stated that there is a pretty little search box that you could have used. Instead, you asked everyone else to search for you and give you the answer. --Kainaw ^(talk) 15:46, 24 January 2006 (UTC)[reply]

I DON'T EXPECT ANYONE TO DO MY WORK FOR ME. I AM NEW TO THE SYSTEM, FIRST DAY EVER USED IT WAS THE DAY QUESTION WAS POSTED. obviously you have little patience with people not as *capable* as you.

Well, you read the instructions well enough to find the reference desk and then post correctly. Most of us don't consider it a stretch to read the please search first instructions. Basically, the reference desk stays fairly busy and we prefer that people attempt to answer their own questions before coming here. — Lomn Talk 19:29, 24 January 2006 (UTC)[reply]

We also prefer that people manning the reference desk be polite to those asking for help, and move on silently if they aren't disposed to help them at the moment. - Nunh-huh 03:45, 25 January 2006 (UTC)[reply]

thank-you for that(Nunh-huh)

Except maybe to point out that it would be nice if people DIDN'T SHOUT. DirkvdM 13:49, 25 January 2006 (UTC)[reply]

not being and internet user i forgot that capitals mean shouting,humble apologies.

Yes, using upper case is considered a capital offence here. StuRat 19:45, 25 January 2006 (UTC)[reply]

And being bold does not mean bold. And being Italian is no excuse to write in all italics. Nor is being big an excuse ... well, you get the idea. :) DirkvdM 20:33, 25 January 2006 (UTC)[reply]

By the way, no-one seems to have pointed out to you that E=mc² is not either of Einstein's theories of relativity, it's Einstein's Mass-Energy Relation. --Canley 04:12, 27 January 2006 (UTC)[reply]

to user: canley, see how much one learns from this forum. thank-you for pointing out that fact. jaclyn

Teleportation and the interruption of consciousness?

I'm sure everyone's seen a sci-fi movie with teleporters, like Star Trek or The Fly. My question is, if the machine is just reading all the cells in your body, and "beaming it" somewhere else (presumably they're destroying the body and transmitting the 'plans' to another body-producing machine), wouldn't this technically kill you? I mean, there would be another person with your thoughts, memories, that was identical, but your brain would actually be destroyed and your consciousness interrupted, so wouldn't you be dead?

I'm uncertain of the concepts behind teleportation and how to phrase my question, but it's a very interesting issue.

Errrr, how should I put this...

Teletransportation does not exist!

Nevertheless, in a hipotetical scenario, it would make an interesting point. I suggest you take a look at Teleportation, specially the Teleportation scenarios section. Enjoy. Mariano(t/c) 14:53, 24 January 2006 (UTC)[reply]

The concept of teleportation was invented by Star Trek, because it was cheap! Just some twinkles and bam, you were on another sound stage. No spaceships to model, no expensive special effects. --Zeizmic 14:57, 24 January 2006 (UTC)[reply]

The concept of converting matter to energy to matter has been studied. You can read tons of boring papers or just get to the point: When matter is converted to energy, it loses any properties it has as matter. For example, when a nuclear bomb explodes, the energy released has nothing in it that signifies that it used to be an nuclear bomb. Also, it is my opinion that the papers that have studied teleportation tend to ignore the fact that the three dimensions we can can touch may not be the only dimensions we exist in. So, teleporting the matter that we can touch may be a small part of our overall existence. --Kainaw ^(talk) 15:43, 24 January 2006 (UTC)[reply]

Not exactly true. Nukes have characteristics which can signify that the energy came from a bomb, and even what the type of manufacture of it was. But this is kind of picky.

There is the issue of transporting the "soul"...at least for those who believe souls are attached to our bodies. Some religious people might very well argue that you have actually murdered the real person and created a souless duplicate. I suspect the anti-stem cell research people would be the ones who would move to have the process banned.

Also, some method would be needed to "jump start" the new copy. That is, the heart beat and other body rythms which had been interrupted would need to be restarted. Your thoughts would certainly be interrupted, perhaps like the shocks in electroshock therapy.

Note that the technology for a very crude transporter exists already. An object can be scanned with a CAT scan or other device, this info can be sent anywhere, then a new object can be created via rapid prototyping methods. The materials are limited to the plastic from the SLA process or the "wood" from the LOM process, and the resolution and size are also limited, and the full process will take hours, but the basic idea is there. All that is needed now are some refinements (which may take a few hundred years) before we can transport people.

Also note that only transporting from one "transporter station" to another would be possible. The idea of transporting to a place without a station to assemble the molecules seems impossible to me. And sending the actual molecules or energy to the new site seems similarly absurd. Only the information need be sent, so that molecules and atoms at the new site can then be assembled into the final object. StuRat 19:55, 24 January 2006 (UTC)[reply]

Kainaw, you said "the three dimensions we can can touch may not be the only dimensions we exist in" and called this a "fact". This doesn't sound right to me. If it were a fact, there would be no doubt about it; but you're only saying it may be true, which leaves a lot of room for doubt. JackofOz 20:17, 24 January 2006 (UTC)[reply]

I was stating the fact of an absense of a fact. I see the confusion. I wonder how often I do that. Regardless, the fact is not that there are more dimensions. The fact is that it is not a fact that there are only 3 dimensions of space. There may be only 3 dimensions of space, but that would only be a theory at this time. To my knowledge, there has been no proof that no other dimensions exist. --Kainaw ^(talk) 02:51, 25 January 2006 (UTC)[reply]

It's a fact that you've really confused me now. There's no proof that 69 dimensions don't exist - does this absence of proof mean that 69 dimensions must therefore necessarily exist? Of course not. I think you're starting by assuming that more than 3 physical dimensions exist and it's up to others to disprove this if they can. Isn't this the reverse of the way the scientific method works? Surely the burden of proof is on those who claim more than 3 physical dimensions. You have to prove this, you can't just assume it is so. Cheers JackofOz 08:53, 25 January 2006 (UTC)[reply]

No, he wasn't saying this means "69 dimensions must therefore necessarily exist" but rather that "some number of spatial dimensions higher than 3 could possibly exist". It's quite clear to me what he was saying. However, I disagree with the implied argument that "if more than 3 spatial dimensions exist, a transportation device would need to account for this to work". Conventional construction methods don't account for additional spatial dimensions, so neither would this be needed for a transporter. For example, if a carbon-12 atom has some presence in a 4th spatial dimension, then either each carbon-12 atom has an identical presence in the 4th dimension, or any differences don't matter to us in the three dimensional world. We know this, because a diamond or other object constructed of carbon-12 atoms is identical, regardless of which atoms we use. Therefore, if we use different carbon-12 atoms at a remote site to reconstruct a person, this difference in atoms will not matter to us in three dimensions. I suppose a philosophical exception could exist if you somehow believe the "soul" resides in this 4th dimension, linked to a set of three dimenional atoms. The argument that the soul will not be transported doesn't require resorting to higher dimensional models of the universe, however, and can stand on it's own. StuRat 10:57, 25 January 2006 (UTC)[reply]

Also note that the technology to transport a retrovirus, some of which are basically just RNA, may exist in just a few years. We can scan DNA or RNA, transmit the info, and assemble DNA or RNA at the other end now. All that is needed is to increase the speed and accuracy to a point where an entire retrovirus can be produced reliably. Some consider a retrovirus to be alive, since they reproduce and evolved from more complex life forms. So, this will be quite a first step toward transporting living things. StuRat 20:37, 24 January 2006 (UTC)[reply]

Boy, has this drifted away from science! I always thought if Star Trek had the perfect replicator, then why destroy the original? Wouldn't it be better to have thousands of Capt'n Kirks running around? or would they ask for too much pay? --Zeizmic 22:22, 24 January 2006 (UTC)[reply]

There's not enough alien ladies for so many! Back, sort of to the topic, I think an interesting question to ask is this: When you go to sleep, is it the same you that wakes up? After all, when you go to sleep, you consciousness gets interupted, and when you wake up you are effectively rebooted and reloaded from memories and so on. (I'm sure some people will disagree with the previous, but it seems to be a fairly common view.) If you accept that sleeping is fine, at least in this worldview, then there isn't anything in particular to worry about with teleportation - should it exist... I guess it ultimately depends on your idea on what consciousness is.

Also, obligatory SMAC quote:

"And what of the immortal soul in such transactions? Can this machine transmit and reattach it as well? Or is it lost forever, leaving a soulless body to wander the world in despair?" -- Sister Miriam Godwinson "We Must Dissent"

--Fangz 00:35, 25 January 2006 (UTC)[reply]

One type of transporter might scan an object, disassemble it, transmit its structure to a remote device, and the remote device construct a new version of the object from its own supply of raw materials. Of course, if the initial device didn't destroy the object after scanning it, you would end up with a copy of the object as mentioned above. In contrast, transporters on Star Trek do not only transmit information. The matter itself is beamed (the "matter stream") to the remote location. This, of course, is why people and objects can be beamed to locations without a transporter, like the surface of a planet; if only information is being transmitted, a receiving device with a supply of raw material must be present. It is also why transporting is limited to a short range around the transmitter; if only information were being transmitted, then presumably one could transmit the information from relay to relay to reconstruct someone many light years away. — Knowledge Seeker দ 01:00, 25 January 2006 (UTC)[reply]

If a "matter stream" were transmitted to some remote location, some device would still be needed to reassemble it. Star Trek neglected this fact as inconvenient. The difficulties in transporting matter and the fact that people are made from fairly common elements would make it rather pointless to send atoms through space rather than just using atoms at the target location.

A transporter that sends info could indeed transport people to locations light years away. However, under current physics theory, this info can go no faster than the speed of light, so the transportation would then take several years. Whether relays are needed would depend on the distance, broadcast signal strength, how narrowly the beam can be kept (perhaps a MASER beam ?), and the sensitivity of the receiver.

Making a copy without destroying the original would effectively be a "replicator", also from Star Trek, but apparently incapable of replicating life forms on that show.

StuRat 04:43, 25 January 2006 (UTC)[reply]

Matter Transmission existed in science fiction "literature" long before Hollywood popularized it and hijacked the terminology, confusing the ethical concepts.

Make a copy, transmit a copy, keep the original ... you have a clone of sorts with identical fingerprints, biometrics, sharing the bank accounts, life mate ... various complications for law enforcement.
- After confirming the copy arrived at destination, kill the original ... some legal complications there if the confirmation was flawed.
- i remember one SF story where the "matter stream" data was "tapped" with an unauthorized copy made, for military intelligence purposes ... take prisoners without it being known that the prisoners were taken.
- There was also a story where the unauthorized copies ended up inside some computer simulation where the prisoner had no free will to resist the interrogation.
- This type of discussion has also occurred in other forums. I remember one where the info needed for replication was to be sent by e-mail, with the discussion identifying all the stuff that could go wrong, based on what can go wrong with our current technology e-mail.
Do not actually copy or kill the original, instead wrap space with a portal or some kind of connection that the people can "walk through." In many hollywood faster than light representations, some kind of worm hole is opened that connects space and time in two places, then the space ship just "walks through" the hole in space. Well perhaps, with suitable protective clothing, a human being could also "walk through."
Then there is teleportation in the psychic sense, where the same effect as the "hole in space" is used without having to know the details.
- There are spiritual variations on this where the psychic mind vision consciousness travels to view some place else in an out of body event.

User:AlMac|^(talk) 13:00, 25 January 2006 (UTC)[reply]

Not to mention that quantum tunnelling could technically cause you to disappear from here and reappear there. The only problems are (1) doing this in a controlled fashion, rather than based on probability, and (2) making sure that all the particles in your body all tunnel to the same relative positions in the same energy configuration at the same time. If you can solve (1) then (2) should be a pushover :) Confusing Manifestation 14:26, 26 January 2006 (UTC)[reply]

Mental Disease of Regret

Does anyone know of a mental disease or disorder which causes a person to intensely regret things which have happened in their life? Particularly things they have done? Captain Jackson 19:03, 24 January 2006 (UTC)[reply]

I'm no psychiatrist, but everyone regrets some things they've done. But if you mean regretting and worrying about things past to the degree that inhibits your ability to function, then it could perhaps be an Anxiety disorder. But there is no way of knowing this, because what you are describing is only one symptom. No mental disease or disorder can be diagnosed merely from a single symptom. --BluePlatypus 19:56, 24 January 2006 (UTC)[reply]

But as you say, BluePlatypus, you're no psychiatrist, so this is hardly an educated opinion. What is your authority for saying "No mental disease or disorder can be diagnosed merely from a single symptom"? JackofOz 20:11, 24 January 2006 (UTC)[reply]

I'm not appealing to authority. I don't need to, nor do I advocate it. If you are educated you can back up your statements with argument and fact. That is both more convincing and useful than any appeal to authority. Also, if you do have authority, you don't have to resort to it, because an authority should be able to argument for their position. That is what seperates science from pseudoscience and religion. As for the arguments in this case, it stands to simple reason: Different disorders can result in the same symptoms. The same disorder can result in very different symptoms. With many disorders, someone can exhibit a single or several symptoms without necessarily having the disorder. If a mental disease or disorder was so simple to diagnose then psychiatrists would hardly even need consulting a patient, or make their diagnosis after a single session. I have never heard of a psychiatrist making such a hasty conclusion. --BluePlatypus 20:38, 24 January 2006 (UTC)[reply]

Well said. StuRat 21:06, 24 January 2006 (UTC)[reply]

Having never heard of something, does not mean that something doesn't exist. Unless you've studied the field of mental diseases, psychiatry etc, you are simply in no position to know whether or not there are any examples of mental diseases or disorders that have a single symptom. I agree that, in general, there is no one-to-one correspondence between symptoms and diagnoses. But for all I know there could be isolated cases where that is true. I've never studied the subject so I would never presume to offer an opinion on that. I leave that to the experts. But I do know that it's not something that can be deduced from reason alone. JackofOz 23:02, 24 January 2006 (UTC)[reply]

Even if there were cases a disorder had but a simple symptom, that doesn't mean that the diagnosis can be assumed from that single symptom. Your argument backs this up because there is just as likely a chance that another disorder could exist that isn't yet known which also exhibits only that one side effect. When you're talking about diagnosis there always has to be a certain degree of assumption involved, and that's the call that needs leaving to the psychiatrists. freshgavin TALK 05:00, 25 January 2006 (UTC)[reply]

The more absolute a claim is, the greater the scrutiny it deserves. BluePlatypus's original statement was nothing if not absolute. All I'm asking is for someone to demonstrate to me that there are no instances where a particular symptom means one and only one diagnosis. Does anybody know that for a fact? If so, show me the evidence. I'm not saying this statement is wrong, I just want to see proof. I'm just applying the same standard of verifiability to this statement as Wikipedia applies to all of us. JackofOz 06:02, 25 January 2006 (UTC)[reply]

I understand what you're trying to say, but if you would think a little bit harder about what you're saying you would see that it can't logically exist. Lets assume the existence of a disease XY is believed. It was discovered when a patient with a very strange symptom GH was unable to get a proper diagnosis and thus they created the designation for XY on the belief that symptom GH was unique. Symptoms could be said to be static, in that no matter when or where you define a symptom, it, if properly defined can mean only one thing. (E.g. red eye doesn't mean black thumbnail and it never will). Diseases and the like are often not static at all, they mutate and change classifications, such that tomorrow a disease called XY-2 might be discovered, and logically you might assume that the symptoms would be similar. Said plainly symptoms could possibly be contained within a finite set, whereas diseases can't be. Yes this is a point in semantics but thinking this way means your statement is slightly less true than the original (you can always assume that there may be another diagnosis even though it is known to exist yet. This is a rewording of your argument.) freshgavin TALK 06:42, 25 January 2006 (UTC)[reply]

Hmmm. I've read your response about 6 times now and still find myself a bit baffled by it, I must admit.

What can't logically exist?

The proof that you're asking for.

If something is inherently unprovable, anybody is entitled to draw attention to that fact. Otherwise, some people will read it and presume it's the gospel truth because it came from Wikipedia reference desk.

You talk about symptoms that, if properly defined, can mean only one thing. And then give an example of a symptom (red eye) that does not mean something else (black thumb nail). The example was not a demonstration of the principle you were explaining, so I'm not sure what you're actually saying here

It was just an example to contrast with diagnosis. Red eye means red eye, not 'red eye v2', or 'suspected red eye', etc.

OK. Then there's no need to introduce irrelevancies like black thumb nail. They just confuse and water down your argument.

"symptoms could possibly be contained within a finite set, whereas diseases can't be" - I confess I have no real idea what this means

Simply that symptoms relative to diagnoses can be easily defined and classified (note: relative) whereas diseases, even when understood take on unpredictable characteristics.

This is not all that much clearer - to me.

"your statement is slightly less true than the original" - what statement? I've made no statements or claims that require testing. All I've done is ask that BluePlatypus's claim be verified.

the original statement was "No mental disease or disorder can be diagnosed merely from a single symptom". Your statement was "You are in no position to know ... if there are examples of mental diseases or disorders that have a single symptom". I'm sure what you meant to say here was "if it is possible to deduce diseases or disorders from a single symptom or not".

And I'm sure I meant exactly, precisely what I said. Blue Platypus told us he was "no psychiatrist". Absolute statements even from experts are always challengeable; how much more challengeable are absolute statements from persons who, by their own admission, are not experts in the field.

"This is a rewording of your argument" - what argument? The only argument I've made is that absolute claims should be subject to scrutiny. How is what you said a rewording of that? JackofOz 11:36, 25 January 2006 (UTC)[reply]

You have made many arguments, in fact I'm losing track. The basic structure of your argument is that it's impossible to deduce A from B when you lack the knowledge to do so, and I'm saying that equally it's impossible to assume that such a one to one correspondence is even POSSIBLE to exist because of the same reason. In fact, I'm not even sure that your argument even EXISTS, or that I'm even argueing about this argument ... ahhh I'm lost in paradoxes. freshgavin TALK 00:43, 26 January 2006 (UTC)[reply]

You changed your argument. First you questioned my authority to make the statement, then you questioned the "absoluteness" of the statement I made. That's inconsistent, because your critique of making an 'absolute' statement is equally applicable to whether it's made by an authority or not. The statement isn't verifiable, however it is falsifiable by counterexample. Not that that matters because you're overinterpreting the statement to make some kind of point. The point of that statement was not to make a dogmatic decree on the nature of all mental illnesses past and present, but to provide the common-sense advice that one should err on the side of caution when diagnosing mental disorders. You are using a Strawman argument, by misrepresenting what I said as an unreasonably absolute statement. --BluePlatypus 15:42, 25 January 2006 (UTC)[reply]

Agreed. StuRat 16:58, 25 January 2006 (UTC)[reply]

Well, no, I didn't change my argument. All I did was restate my requirement for proof in a different way, because my original form of words didn't produce a response that answered the question I was asking. I used the word "authority" in a general sense. (Eg. If you claim "apple" means "orange", I can ask for your "authority" to make such a statement, and if you can produce a dictionary that shows this is a valid meaning, I would be content. I would not require you to engage the services of linguist, grammarian or lexicographer.) You produced no evidence to back up your statement, so I asked further questions.

But even if I had changed my argument (which I didn't), what would have been so wrong with that? If I disagree with something, I'm entitled to challenge it using my entire arsenal of weaponry. If your statement has merit, it will withstand any and all queries.

But that's all water under the bridge now, because you agree that the statement is falsifiable, so I take that as acknowledgment that it would have been wiser never to have made it in the first place.

I never claimed it was an "unreasonably" absolute statement.

I absolutely agree with you that "one should err on the side of caution when diagnosing mental disorders". Perhaps if you had said what you meant right away, we could have avoided this exchange (although I enjoy these debates, I must say, they are very stimulating. If nobody ever took exception to anything anybody ever said, it would be a pretty boring place).

As for the Strawman thing, you're entitled to have that opinion, but that was not where I was coming from (and I think you know better about me by now, BluePlatypus).

Happy Australia Day to all Aussies and everyone else. JackofOz 01:52, 26 January 2006 (UTC)[reply]

Since when did "apple" not mean "orange"? freshgavin TALK 06:55, 26 January 2006 (UTC)[reply]

Hmmm .. interesting question. I guess, as Alice in Wonderland said, words can mean whatever you want them to mean. JackofOz 22:21, 26 January 2006 (UTC)[reply]

I would say Post Traumatic Stress Disorder might qualify.

See Major depression. Feelings of guilt can be a feature of clinical depression. Cybergoth 22:49, 24 January 2006 (UTC)[reply]

One instance of a mental disorder with only one symptom ? what about calling names like empire of evil a free country ? Alas, there are other symptoms. --DLL 18:36, 25 January 2006 (UTC)[reply]

Harvestman, were you replying to my note? I was merely trying to answer the original question. Cybergoth 01:35, 26 January 2006 (UTC)[reply]

I must admit that Harvestman never seems to make any sense to me either. freshgavin TALK 03:47, 27 January 2006 (UTC)[reply]

Suntan through glass windows?

Can you get a suntan through glass windows? Why or why not?

Yes, but not as quickly. Suntan is caused by UV light. While an ordinary glass window will filter out some of the UV, it won't filter out all of it. So it's basically like sunscreen. --BluePlatypus 19:58, 24 January 2006 (UTC)[reply]

Some kinds of glass is largly transparent to UV.

How do whales know where they are going?

Hello. My mother teaches a second grade class and has told her students that they may write down any question that they'd like and put it in her 'mailbox' for her to answer. She has been able to answer all but one of said questions. This question is: "How do whales know where they are going and how do they protect themselves from predators?" I don't really know the answer either so.. please help and, if possible, answer as if you would to a second grade student. Thank you. --Sarah E. Moxley

They nagivate using a form of echo location, like sonar. As for predators, humans whaling are probably one of their biggest concerns. You can find lots more information in the whale article --Noodhoog 20:50, 24 January 2006 (UTC)[reply]

In addition to echo location, they also know where they are by the temperature, saltiness, taste, and currents in the water.

As far as protecting themselves, the adults are generally large enough so nothing messes with them. The adults protect the calves by positioning themselves between the calves and any predators. Some smaller whales, like pilot whales, are small enough to be attacked by sharks. They just have to avoid them. The one thing whales can't protect themselves from is people. Whalers, water pollution, and noise pollution in the form of undersea explosions and SONAR may drive whales to extinction. StuRat 20:59, 24 January 2006 (UTC)[reply]

How do you know they know where they are going? GangofOne 01:50, 25 January 2006 (UTC)[reply]

Because they undergo regular migrations, and seem to make it back to the same place year after year. StuRat 04:36, 25 January 2006 (UTC)[reply]

It seems like I remember hearing something about them also having some sort of magnetic navigation that helps them with migration and things of that nature. Also, if I remember correctly, sometimes when there are solar flares etc., their navigation gets screwed up and sometimes they get lost. I'm not sure how true this is, but take it as you will. I skimmed through the whale article but didn't see anything of this nature. Dimblethum 04:58, 25 January 2006 (UTC)[reply]

Plant diseases

Are 'verticillium wilt' and 'verticulum wilt' the same disease? If not, are they very similar? ike9898 20:33, 24 January 2006 (UTC)[reply]

My guess would be that the latter is a spelling error. Guettarda 21:06, 24 January 2006 (UTC)[reply]

Not sure about that...'verticulum' gets ~245 a few Google hits; if the name variation is just a misspelling, it has apparently propagated. ike9898 22:13, 24 January 2006 (UTC)[reply]

For some of the hits, the html keywords and the contents say verticillium. Maybe a corruption from diverticulum (397,000 hits), same latin root : vertex (summit) ? --DLL 18:25, 25 January 2006 (UTC)[reply]

ac radio controlled power on/off device

I need a type of device that can turn a device plugged into it on and off by radio signal (or some other remote signal). I've heard of devices that can be pre-programmed to turn things on and off, but this won't work for me as I need to be able to turn something on and off at different times every day remotely.

Does anyone know of anything that can do this? Flea110 22:17, 24 January 2006 (UTC)[reply]

"Clap on! Clap off!" See The Clapper. Cybergoth 22:51, 24 January 2006 (UTC)[reply]

I thought of that, but I need a way to covertly switch it. Clapping is much too noticable. 142.179.55.215 23:17, 24 January 2006 (UTC)[reply]

May we ask what you want to turn on covertly ? (I hope it's not a bomb.) StuRat 04:34, 25 January 2006 (UTC)[reply]

Who on Earth would create a bomb that needs a socket nearby? :P ☢ Ҡieff⌇↯ 05:24, 25 January 2006 (UTC)[reply]

A bomb inside a building could work that way. Disguising it as an innocent looking appliance, like a TV, might be effective. StuRat 05:36, 25 January 2006 (UTC)[reply]

But a bomb that needs to be plugged? It just sounds ridiculous :P ☢ Ҡieff⌇↯ 13:54, 25 January 2006 (UTC)[reply]

The idea is that the plug is part of the disguise. You could also make it capable of running on batteries. The plug could also allow an electrical spike to be introduced into the wires to cause an electrical fire in the walls, or, at the very least, cause circuit breakers or fuses to blow. StuRat 16:52, 25 January 2006 (UTC)[reply]

I want to be able to covertly turn on and off the modem connected to the people who live upstairs computer so that at night (or whenever their computer is not in use) I can use a different (but identical) modem with a different phone jack so I can use their internet on my computer. 142.179.55.215 22:11, 25 January 2006 (UTC)[reply]

I'm relieved that it's not for a bomb, but it's still unethical and quite possibly illegal to do what you want, so I advise against it. Also, if they catch you they may be furious. It hardly seems worth the risk. Why not ask them about sharing their internet connection ? They may ask you to pay half, but at least you will be honest about it. StuRat 05:11, 26 January 2006 (UTC)[reply]

I didn't want to have to admit this (because it sounds childish sort of) but "the people who live upstairs" are my parents. They are strictly against me using the internet on my own computer. Don't ask me why, as in my opinion they've presented no reasonable reasons. I've tried endless negotiations with them, but to no avail. True, if they catch me they would be furious, but I can see no other reasonable alternatives. It's not a matter of payment at all, it's just that, in their opinion, me+internet on my own computer=bad news.

You need to decide which is more important, having Internet access on your computer or gaining your parents' trust and respect. This type of action, if discovered, will seriously damage the trust and respect you should be trying to foster. Since you obviously have Internet access to be posting here, I am guessing they allow you to access the Internet on their computer. This is standard advice given to parents: "allow kids to use the Internet, but only with supervision, to be sure they don't get into trouble online". I know it's hard to accept, but they are just doing what they think is best for you. StuRat 08:54, 27 January 2006 (UTC)[reply]

Perhaps this isn't the best place to carry on a discussion of this sort. See your talk page. Flea110 23:38, 27 January 2006 (UTC)[reply]

Have you looked into X10 automation? Many systems offer manual remote control.Night Gyr 23:27, 24 January 2006 (UTC)[reply]

The issue is "radio controlled". Radio controlled devices are highly untrustworthy. Just about any cell phone, microwave, passing airplane, or errant television signal can set them off. If you can accept that, it isn't much of a device. Any hobby shop has tons of radio controlled on/off switches (like a servo, but it is either on or off, not a swinging arm). Connect that to the control of a relay and it will turn the relay on and off. You'd want one that is commonly used to turn AC/Heater systems on/off. Those relays easily handle standard AC load. --Kainaw ^(talk) 23:52, 24 January 2006 (UTC)\[reply]

He wants a device he can plug in and use, not something he has to jury rig himself. X-10 provides exactly what he wants. Also, your fears of setting off radio controls are rather unfounded. The FCC keeps the frequencies reasonably well regulated, at least as far as noninterference goes. I don't see garage doors opening every time a plane takes off. I've never seen a single report of X-10 devices being turned on or off by outside interference. Night Gyr 23:57, 24 January 2006 (UTC)[reply]

I have seen many interference problems. But then, I have always lived near the biggest RF polluter that I know of - airports. It was worst when I was in the Marines living on an air station. There was so much pollution that our speakers would emit strange buzzing noises all day even if they were not plugged into anything. As for garage doors - funny you should mention that. As a stupid teen, my friend and I would drive through neighborhoods with an RF emitter and open garage doors one after the other. I know they are better now, but back then they would open for just about any signal. --Kainaw ^(talk) 02:45, 25 January 2006 (UTC)[reply]

Here's a few X10 devices that take RF control: [11] You may want to shop around for lower prices, but you're only looking at around $20 for a simple remote plugin switch. Night Gyr 00:00, 25 January 2006 (UTC)[reply]

I will definitely be looking into this. Thanks. Flea110 02:56, 25 January 2006 (UTC)[reply]

Many terrorists have used bombs attached to cellular phones. So long as the batteries in the phone hold out, telephoning the cell phone, it rings, the ringer is attached to the boom.
Some security services use devices activated by voice or motion detection, so that they are only capturing information, when there is information to be captured.
In the business computer world, we can send messages to dummy addresses that are being monitored by software. No message, no action. Message arrives, and the software processes it. The message can be quite simple, containing some text strings that are like commands to the monitoring software to tell it what to do.

User:AlMac|^(talk) 13:15, 25 January 2006 (UTC)[reply]

Years ago I bought a device on sale from Radio Shack which did this. I had a light in the garage where the switch was

located in an incovenient place so I hooked this up to it and hung the on-off switch next to the door. The switch needed a standard 9v battery and had a simple on button and an off button.

Garage door openers are pretty popular ... motorist enters driveway & clicks the thing ... it can also be hooked to the house lites so you not have to get out of your car at nite to find the light switch. Many people have clutter in their garages that are easily tripped over. User:AlMac|^(talk) 04:22, 26 January 2006 (UTC)[reply]

January 25

Sex-linked diseases

Why aren't there sex-linked diseases that are carried on the Y chromosome (or are there)?

I think this is a plot by the female gender. (CABAL!) — Ilyan e p (Talk) 01:31, 25 January 2006 (UTC)[reply]

Because there is little essential information carried on the Y chromosome. Every human has an X, but 50% of the human race lacks a Y, so it has to be dispensable. The only significant Y linked disease is the absence or nonfunction of SRY, which leads to sex reversal (XY genotype, female phenotype). It's a genetically "dead-end" condition because they are usually not fertile. alteripse 01:38, 25 January 2006 (UTC)[reply]

Also, I'm fairly cetain that there are some, though not many. The reason for this is twofold. One, any major life-threatening diseases can only be transferred directly from father to son. Another is that there are no carriers. Females aren't affected by sex-linked diseases as much because most of those diseases are found on the X chromosone. Since they have two X chroms, unless both chroms are affected, the unaffected X chrom just takes over. In this way, they have a chance of being unnafected but passing on a defected X. An affected Male Y chromosone doesn't have another Y who can take over. --Herzog 01:44, 25 January 2006 (UTC)[reply]

Note that this is only true of recessive diseases carried on the X chromosome. StuRat 04:24, 25 January 2006 (UTC)[reply]

Several types of azoospermia are linked to mutations in genes on the Y chromosome. But because these conditions decrease fertility, there is a strong evolutionary bias against them. --WS 13:14, 26 January 2006 (UTC) The Sex linkage article comes close to defining sex-linked disease genes as being on the X chromosome. Some genetics texts seem reluctant to describe Y-linked defects as sex-linked disease (example). Some people say, "All sex-linked disorders are X-linked" (example). --JWSchmidt 02:15, 25 January 2006 (UTC)[reply]

The way we were given sex-linked diseases was basically a disease that is carried on the X chromosome. — Ilyan e p (Talk) 03:01, 25 January 2006 (UTC)[reply]

There are unique genes on the Y chromosome. I believe that mutations on these genes might cause certain diseases, such as azoospermia and male infertility. See also genetic disease and y-linked disease. See here for a list of genes on the Y chromosome. Cybergoth 04:17, 25 January 2006 (UTC)[reply]

Thanks for the list. I added them to Y chromosome. alteripse 11:21, 25 January 2006 (UTC)[reply]

Flashlights that you shake

I keep seeing these ads for flashlights that you shake to light up, that supposedly don't need any batteries. How do they work, and how long does the light last after each shaking? User:Zoe|^(talk) 03:40, 25 January 2006 (UTC)[reply]

I think the most important part is that they use a much higher efficiency light than a conventional flashlight's incandescent bulb. This allows the small amount of energy from shaking to last longer. StuRat 04:18, 25 January 2006 (UTC)[reply]

They use LEDs. I don't have a "shaky" flashlight, but I do have one that you "wind up". After about 30 seconds of winding, it provides 3-5 minutes of useful light. (I'm always amazed that it actually works, so the short duration isn't too bad). I'd be surprised if the "shaky" light lasted any longer than that. - Nunh-huh 04:23, 25 January 2006 (UTC)[reply]

The shaky flashlights contain a mobile magnet and a wire coil that runs along the length of the interior of the flashlight. When you shake the flashlight, the magnet moves up and down along the coil, inducing an electric current in the coil. This current is stored by the flashlight in a capacitor–for short-term, low energy storage, capacitors are more efficient than batteries)–and used to operate a high-efficiency LED. Some companies report sufficient storage capacity to remain lit for up to 60 minutes without additional shaking. TenOfAllTrades(talk) 04:38, 25 January 2006 (UTC)[reply]

Is it just me or does anyone else find it amusing that a bunch of people who are, presumably, adults are referring to something as a "shaky flashlight"? I don't know... Just reminds me of the Monty Python bit that discusses the parts of the body including the "naughty bits". Dismas|^(talk) 10:17, 25 January 2006 (UTC)[reply]

I've seen and used those flashlights, and their appearance is just as suggestive as you allude to above. Some friends of mine coined the term "wanklight" for them. (This is getting more appropriate for Urbandictionary than Wikipedia, though, but since we're technically in projectspace I suppose it's okay to get sidetracked into "Ehehehehe, that thing looks like a... penis!" occasionally. Let's try not to make a habit of it, though.) —Ilmari Karonen (talk) 11:29, 25 January 2006 (UTC)[reply]

Fleshlight comes to mind.... ☢ Ҡieff⌇↯ 11:38, 25 January 2006 (UTC)[reply]

One of my friends owns one and brought it on a recent camping trip; we all agreed that 'charging the flashlight' would be an excellent euphemism. TenOfAllTrades(talk) 13:01, 25 January 2006 (UTC)[reply]

Sounds pretty impractical to me. Doesn't the light bounce all over the place when you shake the torch (I mean, when you start using it and the battery is still empty)? A Dyno torch seems to make more sense. And they've been around for at least half a century, so what might this new invention have to offer? The article mentions it and says it uses a 'solenoid'. It also says these new things are less reliable, so I'll stick to the torch I have. Which, by the way, is exactly the same one as the one in the photograph. And a bit of trivia: the Dutch word is 'knijpkat', meaning 'squeeze cat'. Apparently, the dynamo used to make a sound reminiscent of a 'squeezed cat' (or so the Dutch article claims). Luckily that is no longer the case. :) DirkvdM 14:16, 25 January 2006 (UTC)[reply]

Come to think of it, this might be practical for travelling. Both models have the advantage that one is not dependent on an electricity source. But the shaken version will load itself in a backpack by being bounced up and down (and sideways occasionally :) ). But then wouldn't something that loads recharchable batteries (which can also be used for all sorts of other things) make more sense? DirkvdM 14:25, 25 January 2006 (UTC)[reply]

Oh, and that makes me think of watches that charge themselves through a rotating motion. Simply wearing them (and moving your arm often enough) charged them. Haven't seen any of those for some time though, which makes sense in this age of 'digital watches'. DirkvdM 14:36, 25 January 2006 (UTC)[reply]

Isn't it based on Faraday's law of induction concerning induction of charge by a ferromagnetic object moving against a coil? These are neat little devices, but the capacitors seem quite limited and only hold a charge to run a LED for a brief period. I was rather disappointed in the actual light output of these devices, its quite minimal. IMHO, unless you have the need for a truly free energy source thats going to last a very very long time, you are a lot better off just getting a LED based lithium-ion battery powered light. They will shine for a *really* long time, plus they are very bright and compact. I found an 8-led light that takes 3 AAAs, its rated to shine for 100+ hours on a set of batteries, it is blinding bright, and about 1" dia. x 4" long, very small for a flashlight. --66.195.232.121 19:00, 25 January 2006 (UTC)[reply]

The issue I have with conventional flashlights is that I may only use them once every 10 years, when I have a long power failure, at which time the batteries are invariably dead from age. Any alternative to battery powered flashlights can solve this problem. Of course, I could always periodically go around and check all my battery charges, but that would take away from my ranting time here. StuRat 19:36, 25 January 2006 (UTC)[reply]

I have a similar problem, after about 10 years I can be assured that the entire flashlight is gone. I don't think ive posessed any one thing for longer than 4-5 years, and thats when its something hard to lose. Flashlights are usually out of my posession before they are ready for new batteries. If someone could invent the self-retaining flashlight thats resistant to 'forgetful borrowing roomates' and 'disappears when placed in a large box marked MOVING' that would be of *great* use to me.

I think you need to "borrow" your roommates' girlfriends, at least until they stop borrowing your stuff. StuRat 12:57, 26 January 2006 (UTC)[reply]

Do your roommates 'borrow' your lightbulbs as well? If not, then you might hang the torch from the ceiling, pretending to be a lightbulb. This way it's also easier to locate when you need it. DirkvdM 10:42, 26 January 2006 (UTC)[reply]

Thanks for all the answers, folks. User:Zoe|^(talk) 17:08, 26 January 2006 (UTC)[reply]

Quantum Mechanics and General Relativity

In the equation, hf = mc^2, what is the underlying principle? How can mc^2, associated with a stationary mass, be linked with hf which has a certain frequency? Does that mean that even a stationary mass also have a certain oscillation within them, thus providing them with a certain energy hf?

E = hf represents the energy E of a photon of frequency f (h being Planck's constant). E = mc² represents the rest energy E of a certain amount m of mass (c being the speed of light on vacuum). While they're both energy, I don't think you can equal both because they're about two different concepts: photon energy and rest mass energy. I don't recall seeing the equation "hf = mc²" before either, so I may be utterly wrong. But.... On a second thought, with mass being the same thing as energy (E=mc²), and a photon having energy (E=hf), you could understand that a photon would suffer the effects from gravity the same way ordinary mass does, which is true... Would that be correct? :P ☢ Ҡieff⌇↯ 07:18, 25 January 2006 (UTC)[reply]

E=mc^{2}

doesn't apply to photons, because they have no rest frame. However,

E={\sqrt {p^{2}c^{2}+m^{2}c^{4}}}

applies to everything, giving

E=pc={\frac {hc}{\lambda }}=hf

for photons (and

E=mc^{2}

for stationary particles with mass). See De Broglie wavelength for why

p={\frac {h}{\lambda }}

(h being Planck's constant), and for discussion of how to assign a sensible frequency/wavelength to particles with mass. As far as I know, there is no intuitive way to relate any of this to General Relativity--it's much easier just to think of all particles as following the curvature of spacetime. -- SCZenz 16:07, 25 January 2006 (UTC)[reply]

See my note above, and the De Broglie wavelength article. Since

\lambda ={\frac {h}{p}}

, a motionless massive particle really wouldn't have a wavelength. That likely explains why we've never seen

hf=mc^{2}

. -- SCZenz 16:11, 25 January 2006 (UTC)[reply]

The equation could be used to calculate the frequency of a photon emitted in a matter-antimatter decay. Be careful about the number of particles though. -lethe ^talk 18:52, 25 January 2006 (UTC)

I seem to recall the equation

mc^{2}=hf

originated in the 1965 movie Alphaville, where some pseudo-scientific calculations are interspersed with the movie, resulting in the above equation -- Ferkelparade π 11:41, 26 January 2006 (UTC)[reply]

About the hydraulic model of inductors

From the article inductor:

"As electrical current can be modeled by fluid flow, much like water through pipes; the inductor can be modeled by the flywheel effect of a turbine rotated by the flow. As can be demonstrated intuitively and mathematically, this mimics the behavior of an electrical inductor; current is the integral of voltage, in cases of a sudden interruption of flow it will generate a high pressure across the blockage, etc. Magnetic interactions such as transformers, however, are not modeled."

My question is quick: would the energy stored on the magnetic field of the inductor be then akin to the angular momentum stored on the flywheel?

If so, then why cannot we model magnetic coupling? Wouldn't that be akin to the coupling of two flywheels through the use of gears? I suppose you could model the magnetic induction on a secondary through the transmitted torque on the gears.

Just a thought... ☢ Ҡieff⌇↯ 07:05, 25 January 2006 (UTC)[reply]

Hmm, at a first glance, the coupling thing does look like a really good equivalance. deeptrivia (talk) 13:43, 25 January 2006 (UTC)[reply]

BTW, it's spelled hydraulic. StuRat 16:45, 25 January 2006 (UTC)[reply]

D'oh ☢ Ҡieff⌇↯ 00:08, 26 January 2006 (UTC)[reply]

Hight Def Video and Interlaced format.

What is the technological reason for using any interlaced video format with HDTV? As far as I understand the interlacing technique was invented to get around the fluorescent's short persistence phenomenon, in order to reduce flickering on Cathode Ray Tube displays (CRTs). With the invention of the plasma screens and since HDTV targets mostly those screens, this technique seems to be obsolete and not necessary anymore (plasma screens do not suffer from the short persistence like CRTs). I expected any new format to abandon the interlacing technology completely and concentrate on compression using the modern technology (Spatial / Temporal redundancy reduction using Motion Compensation and DCT). Transmitting 60 fields per second or 30 full frames per second consumes the same bandwidth however if the video is interlaced the receiver must de-interlace it, which consumes serious amount of CPU power and result in inferior quality.

Why we are still using interlaced video for HDTV???

Hkl8324 08:23, 25 January 2006 (UTC)[reply]

Good question. I'm not actually sure, but one thought is in dealing with missing chunks of a picture due to interference. Having a large black chunk in the middle of the screen during a frame would be far more obvious than two "half-black" chunks. Also, this would provide the receiver the potential to reconstruct the missing pixels by averaging the pixels above and below, which should make the missing data completely undetectable to the veiwer at normal speed and difficult to detect even in a freeze frame. I don't know if any receivers currently have this ability, but interlacing at least makes it possible. Without interlaced images, the next best thing would be to average the previous and subsequent frames. This would have the disadvantages of requiring 3 frames be stored in memory rather than one, requiring a delay of one frame before each frame is displayed, and would also do a poor job of filling in a quickly moving object in the missing field. Again, I don't know that this is the reason, it's just a guess. StuRat 10:28, 25 January 2006 (UTC)[reply]

EYE

Is the power of eye sight at any stage constant; means I am now 24 and using glasses of power -1.75 for right eye and -1.25 for left eye, Is it chages frequently or it may constant for long time in constant use.

waiting for valuable suggesstion, thankx

It can change over time. Typically glasses will last several years, but you should be retested regularly. As well as getting weaker or stronger, other things change with age (often in the 40-50 age group) such as difficulty focussing on closer objects when wearing glasses that are needed for far objects; this leads to glasses with multiple prescriptions. Notinasnaid 10:56, 25 January 2006 (UTC)[reply]

You should go back and get retested at least every two years or so (yearly until about the age of 18). Your prescription isn't especially high, and so I wouldn't imagine it would change very rapidly. Wikipedia does not dispense medical advice, however, and so for correct advice, please consult your opthamologist/optician/optometrist. You will find that your vision will get better in the short distances as you get older (40 or 50 as Notinasnaid said), but your long-distance vision will weaken. See eyeglass prescription, myopia and hyperopia for more information. Proto t c 12:19, 25 January 2006 (UTC)[reply]

arterioschlorosis

Does the onset or acuteness of arterioschlorosis have anything to do with long-term consumption of hard water?

Dudley Warrington

You had me 'suitly emphazi'd' for a while until I realized its atherosclerosis, which is gunking up of the arteries. This comes more from eating junk food than anything else. --Zeizmic 15:46, 25 January 2006 (UTC)[reply]

+10 points for using "the words". ;) --Sum0 15:53, 25 January 2006 (UTC)[reply]

Hard water could possibly clog water pipes, but not "your pipes", AKA veins and arteries. Trans-fatty acids, like partially hydrogenated soybean oil, is the main culprit there, and should be avoided entirely. StuRat 16:39, 25 January 2006 (UTC)[reply]

There have been several laboratory and epidemiologic studies that have correlated the long-term consumtion of hard water with a decreased risk of cardiovascular disease. This is mostly considered a result of the physiologic effects of dissolved calcium and magnesium in hard water. There is also some ambiguity in the use of the terms "hard" and "soft", since they mostly refer to the reduced detergency of surfactants in water rather than a specific set of dissolved minerals. Therefore, "soft" water need not simply have a low concentration of known hardeners such as calcium, but may have elevated levels of substances such as lead or cadmium, which are quite toxic. See Water & Heart Disease--Mark Bornfeld DDS 16:50, 25 January 2006 (UTC)[reply]

Softened water is also frequently high in sodium, which can cause high blood pressure, which in turn damages blood vessel walls and provides sites for the formation of atherosclerosis. However, the amound of sodium is usually less than that consumed in the typical unhealthy diet. StuRat 19:29, 25 January 2006 (UTC)[reply]

singularity????where from

i one of the q&a i read about singularity. But where did this matter come from?????(big bang theory)

If you're referring to the "singularity" from which all matter came at the start of the universe, I'd caution that we don't know what happened in the first tiny fraction of a second of the universe's existence, and we probably never will. The moment of the Big Bang was the appearence of the universe, space, and time—not just matter—and I it's not even clear that science can answer the question of where the universe itself came from.

Of course, there are also run-of-the-mill singularities, i.e. Black holes. -- SCZenz 16:15, 25 January 2006 (UTC)[reply]

LOL @ "run of the mill black holes" ... I have a few dozen in my closet right now. StuRat 16:35, 25 January 2006 (UTC)[reply]

They're easy to make, if you happen to have a star of a couple solar masses with a nearly all-iron core lying around. -- SCZenz 16:40, 25 January 2006 (UTC)[reply]

Yes, I always keep several solar masses of matter handy in case I need to create a black hole Ad Hoc. In fact I have an interesting story about the time I accidently...

Unusual frog

I'm looking for the name of a frog (or possibly a toad) I saw on a nature show. It had a distinctive leaf-shaped body, and the female had a section of sponge-like skin on her back where she kept the tadpoles until they matured. The skin had large pores in it where the tadpoles could swim in and out. I'm not having any luck finding its name by searching for the characteristics. TheSPY 14:45, 25 January 2006 (UTC)[reply]

Was it one of the malaysian frogs on this page? David Sneek 15:54, 25 January 2006 (UTC)[reply]

Surinam Toad? Femto 19:59, 25 January 2006 (UTC)[reply]

Many thanks! TheSPY 20:23, 26 January 2006 (UTC)[reply]

PC to MAC file conversions

I currently own a Dell laptop running Windows XP. I have saved pictures, music (iTunes and Media Player) and documents etc... What is involved and how difficult/frustrating/time consuming would it be if i bought an Apple computer and wanted to transfer everything to that. Thank you, Dan l'homme

JPGs, BMPs, GIFs, MP3s, plain text files and PDFs can be viewed/heard with the software that comes with Mac OS X. I imagine your problems will be more an issue of finding appropriate software than with converting files (example, Windows Media player for mac for WMVs). Frencheigh 15:38, 25 January 2006 (UTC)[reply]

I don't have any personal experience with this, but I would imagine that DRM-protected music files in iTunes might also cause you some problems. As for documents, proprietary formats will be difficult to transfer if there is no compatible program for the Mac. — QuantumEleven | (talk) 16:40, 25 January 2006 (UTC)[reply]

There is no "etc" in this sort of task. You need to look at every type of file involved, sadly. Notinasnaid 19:35, 25 January 2006 (UTC)[reply]

Something Cernen's familiar with. (And, being Cernen, I can answer your question, even though I'm too addicted to Wikipedia for my own good). If you want to convert WMAs for use on a mac, you can't do it on the mac. I've tried. You have to do it from Windows using iTunes and then take the newly created stuffs from your Windows PC to your Mac. The DRM-protected music in iTunes (m4ps) won't cause you any trouble at all if you register your new iMac with your iTunes Music Store account (a very easy task). If, however, you have stuff you bought from the RealNetworks music store, you can either kiss it goodbye or go through the long arduous process of burning it to a CD, then ripping the CD on your Mac. (A royal pain in the arse.) To transfer files, I took my hard drive out of my old computer and put it in a portable enclosure; you can find those just about anywhere for about forty bucks. I plugged the enclosure into my Mac and took the files off of it that way. (Keep in mind, however, that while reading from Windows XP hard drives is a piece of cake for a Mac, writing to them can be deadly and you should not do that at all.) 12.72.244.198 12:12, 26 January 2006 (UTC)[reply]

What would the Move2Mac software allow me to transfer?

What would be missing? Thanks, Dan l'homme

My recommendation is NOT to use Detto Move2Mac. From all the reviews posted at the Apple Store by people who have used the product, it is generally hated. I don't know what it would or wouldn't allow you to transfer, but you could check their website for more information. 12.72.244.198 12:32, 26 January 2006 (UTC)[reply]

Thank you for all your advice. You'd like to think there'd be a simple answer. Dan l'homme

Do wind turbines causea magnetic fields?

(no question posted)

They can if that is what they are designed to do. See wind turbine. --Kainaw ^(talk) 19:57, 25 January 2006 (UTC)[reply]

muscle is less heavy than the fat

Is it true that the muscle is less heavy than the fat ?

I've always heard that muscle is heaver than fat. Dimblethum 23:25, 25 January 2006 (UTC)[reply]

It seems muscles are 22% more dense that fat, thus 1 cubic centimetre of muscle is heavier than 1 cubic centimetre of fat. - Akamad 23:55, 25 January 2006 (UTC)[reply]

That's correct. This leads to the odd fact that when starting an exercise program, a person may lose inches off their waist, and yet gain weight, as the fat is transformed into muscle. StuRat 02:22, 26 January 2006 (UTC)[reply]

'transformed' may not be the right word, though it leaves one with a useful mental image. -- Ec5618 10:22, 26 January 2006 (UTC)[reply]

Reheating spinach

I've heard that reheating spinach makes it toxic. The spinach article says nothing about it and a question at the talk page hasn't gotten a conclusive answer. Anyone here know? The reason I ask is that I regularly eat (frozen) spinach, to which I add milk, feta and lemon juice, which requires reheating. If there is any truth in the story, does it apply to this or only to serious cooling (eg in the fridge to eat the next day)? Oh, and to complete the recipe, I also add curry powder (a fair bit of the stuff), an egg and an onion, mash that with boiled potatoes and eat it with black pudding. Absolutely delicious! DirkvdM 20:24, 25 January 2006 (UTC)[reply]

Ok, you crazy old guy, you made me use some of my very suitly emphazi time. Spinach contains oxalic acid, which has some nasty properties. However, when washed down with large quantities of good Dutch beer, it is quite safe to eat, reheated or otherwise. --Zeizmic 21:53, 25 January 2006 (UTC)[reply]

I've never understood why people cook spinach. Raw it is much better for you and better tasting than lettuce. When cooked, however, it acquires the texture of snot. StuRat 02:17, 26 January 2006 (UTC)[reply]

Agreed. Though spinach/potato soup is pretty good. ☢ Ҡieff⌇↯ 05:08, 26 January 2006 (UTC)[reply]

And don't forget to try it with curry (or curry powder). Actually, the packaging states that the spinbach has merely been briefly blanched and I don't cook it, just heat it. I now notice that the quantity I eat in one day contains just over the daily recommended dose of vitamin A (1 mg), so I suppose I should be a bit careful with that since that can be bad for the liver (although it's still 1/3 of what the article states as the upper limit). Oh, and I now remember once hearing that adding an egg counteracts the alledged negative effects of spinach. Another old wives tale? DirkvdM 11:04, 26 January 2006 (UTC)[reply]

Spinach salad is good. Make a dressing of hot bacon grease and chopped bacon bits with vinegar and pour it over the leaves, they slightly wilt. Excellent salad. :) User:Zoe|^(talk) 17:11, 26 January 2006 (UTC)[reply]

Ah, yes, bacon! I used to put bacon in it, but I ate bacon in half my meals and I didn't want to leave it out of the chili (chili con bacon :) ), so I left it out of the spinach. Oddly, that's how I came up with the currypowderm looking for an alternative flavouring. Two fine examples of how I think I came up with something original, only to find out others have thought of that too. DirkvdM 10:20, 27 January 2006 (UTC)[reply]

While I am a big raw spinach fan and never eat iceberg "lettuce" if I can avoid it, I became a big fan of cooked spinach for the first time in the form of palak paneer sometimes called saag, though the picture in that is different from how I have usually had it. DirkvdM, you should try that as it's kind of like what you make. I've certainly never heard anything about reheating it being dangerous. Where did you hear that? And it seems our [[spinach article could use some verifying. The nutrition bit seems a bit off, but I have no reason to know for sure. - Taxman ^Talk

Book needed

Greetings:

Does any one know where I can find a electronic copy of the following book? :

Software Testing: A Craftsman's Approach, Second Edition
2nd edition,
Paul C. Jorgensen,
CRC Press

I need it desperately for my upcoming software engineering class midterm.

Regards,

129.97.252.63 21:48, 25 January 2006 (UTC)[reply]

I will not make fun of people who ask for illegal things... I will not make fun of people who ask for illegal things..... --Zeizmic 22:50, 25 January 2006 (UTC)[reply]

What makes you think it's illegal?...What makes you think it's illegal?... DirkvdM 11:09, 26 January 2006 (UTC)[reply]

Get a digital camera.
Break into the school bookstore.
Locate the book and photo all the pages with your camera.
When you are sitting in the jail cell later, if they let you have access to your camera, you can then study the electronic copy in there.

User:AlMac|^(talk) 04:25, 26 January 2006 (UTC)[reply]

I think the point is that most recent books are not available electronically, precisely because of the fear that they will be illegally copied and deny the authors their royalties. There are exceptions, however. I don't know if this book is an exception or not. StuRat 12:51, 26 January 2006 (UTC)[reply]

Indestructible penguins

I've heard that penguins resist extreme low temperatures because they have an ultra-dense layer of fat under their skin. Could you acknowledge this? --GTubio 22:11, 25 January 2006 (UTC)[reply]

Nothing that is ultra-dense would make a good insulation. However, the outer feathers mat to a dense layer to keep out the water. Then they have a fluffy layer of down, and a layer of standard blubber. Our article penguin does not go too much into the physics of the insulation. I found that from other sources. --Zeizmic 22:48, 25 January 2006 (UTC)[reply]

How ultra-dense layers of fat would characterize anything as indestructible? (Blob!?) ☢ Ҡieff⌇↯ 05:06, 26 January 2006 (UTC)[reply]

Apparently that was meant as a humorous exaggeration. StuRat 12:46, 26 January 2006 (UTC)[reply]

Fat is lighter than water, so it can't be particularily dense in comparison with the rest of an animal. --BluePlatypus 16:18, 26 January 2006 (UTC)[reply]

Thank you all. And... yes, it was an easy joke (although some people didn't even get it) to attract people in a manner "what the heck is this section going to be about?". --GTubio 17:14, 26 January 2006 (UTC)[reply]

I figured it was just a stupid attempt at an addition to Exploding animals, which is so Wiki2005. freshgavin TALK 03:42, 27 January 2006 (UTC)[reply]

Characteristics of human eyesight

Is it possible to express human eyesight characteristics as measures of resolution, contrast ratio, etc...? For example, does it make sense to say something like "human eyes see in 2000x3000 resolution, with a 10000:1 contrast ration"? If so, what do humans see in? Flea110 23:43, 25 January 2006 (UTC)[reply]

Somebody asked that question a few days ago and it was answered here. freshgavin TALK 00:03, 26 January 2006 (UTC)[reply]

When I click on the link, it merely takes me to the main science page. Is the problem with me or with the link? Flea110 00:12, 26 January 2006 (UTC)[reply]

The link was wrong. He wanted to direct you to Wikipedia:Reference desk/Science#eye_compared_to_a_camera. ☢ Ҡieff⌇↯ 00:34, 26 January 2006 (UTC)[reply]

Unless you edited it, the link was right. You have to wait for the entire page to load before the focus shifts to the anchor. [sp?] freshgavin TALK 00:51, 26 January 2006 (UTC)[reply]

Yeah, I edited it. ☢ Ҡieff⌇↯ 01:43, 26 January 2006 (UTC)[reply]

Ah, right. I see my mistake now. m(_ _)m freshgavin TALK 04:23, 26 January 2006 (UTC)[reply]

January 26

Specific question help.

Before people start shouting "NO HOMEWORK" at me, I'm aware it's against the rules - but I figure I've nothing to lose by trying :)

The lab this week was reducing benzil to form a diastereoisomeric diol, then determining which form you got (RR, RS, SS.) I've solved all the subsequent problems to do with the formation of a cyclic ketal, and I'm certain that the product I got was meso-, but I can't figure out why it was. I'm guessing there has to be some sort of steric factor, but that alone isn't going to cut it in a write-up, and playing around with my models, I can't see why only the meso-form is produced from the reduction. Any hints from the amazing Wiki-mind? 81.132.176.76 01:18, 26 January 2006 (UTC)[reply]

Usually there's no problem with homework, it's just in the way you phrase your question. For example: What are the side effects of a pshydoplastic endomiam at room temperature and what will be the moral setbacks to newborn babies? is a badly asked question because it looks like it was taken right out of a textbook. You've obviously TRIED the homework and you're stuck at a relatively minor point, so you're merely asking for help, rather than asking for it to be done. Unfortunately, I have no clue, so wait for someone else : ). freshgavin TALK 04:19, 26 January 2006 (UTC)[reply]

Never mind, I figured it out. It's just general stereoselection for reduction of ketones, attacking from the less-hindered side. Not sure why I didnt think of it in the first place, to be honest :)

Yep, you've got it. The incoming "hydride" (δ−ve hydrogen) has a choice between coming in past a δ−ve oxygen or coming in from the other side unhindered: it tends to come in from the other side. Physchim62 (talk) 13:03, 27 January 2006 (UTC)[reply]

head-to head clinical trials

What is a "head to head" clinical trial?

Matching two similar treatments to see which is better. For example, recruiting the next 20 patients with ear infections for a trial. Randomize 10 to receive 10 days of stompicillin, and give the other 10 patients 10 days of homeopathic gopher pellets. Measure all the relevant clinical parameters you can think of, such as fluid remaining in the ear at 10 and 20 days, number of days until pain gone, number of days until fever gone, number of days of school or work missed, and so forth. If this was your idea, you write it up for a medical journal. If this was sponsored by the makers of stompacillin they either publicize the results to every doctor in the US or bury the results (depending on the results of course). alteripse 02:36, 26 January 2006 (UTC)[reply]

That doesn't seem like a very good testing method. First, 10 patients is so small of a sample that wild variations would be expected in results of repeated trials. But even with a reasonably large sample, all you prove is whether stompicillin is better or worse than gopher pellets. If gopher pellets are of no use whatsoever, or even harmful, then being better than gopher pellets isn't showing much. On the other hand, regulatory agencies such as the US Food and Drug Administration regularly approve meds which are less effective and have more side effects than existing treatments for the same condition. Perhaps such a test would discourage these approvals. StuRat 04:41, 26 January 2006 (UTC)[reply]

The necessary size of the trial depends on the magnitude of the difference you want to detect. A head to head trial simply compares two treatments against each other. It is not intended to prove effectiveness of either against no treatment. alteripse 04:54, 26 January 2006 (UTC)[reply]

Further to Alteripse's point, interpreting the validity and importance of scientific studies is a very complex issue. That's why media reports based on a science journalist flipping through Nature or the New England Journal of Medicine, reading the abstract of some paper or other, and immediately jumping to conclusions, drive scientists batty. --Robert Merkel 08:10, 26 January 2006 (UTC)[reply]

And in either event, the sales of gopher pellets will continue... - Nunh-huh 04:25, 26 January 2006 (UTC)[reply]

Indisputably. alteripse 04:55, 26 January 2006 (UTC)[reply]

Cricket lifespan

I was just curious how long the average species of cricket lives. Anybody?

Google it freshgavin TALK 04:13, 26 January 2006 (UTC)[reply]

Satellite cover

How many satellites do you need to be able to see the whole surface of a planet from at least one of them at any moment? If the size of the planet matters, it's about half earth radius. My first guess was three (in GSO) but I don't think you'd be able to see the poles (esp. if there are valleys, etc. --대조 | Talk 06:10, 26 January 2006 (UTC)[reply]

It depends if you're talking 'metaphorically' or if you want a solution for the real world. If you think about it logically, you could see the entire world with only 2 sattelites at a fair distance, although as you said the poles (or the equator, if they were positioned at the poles) wouldn't make out very well. I don't think you'd lose much visibility because of mountains, valleys, but you'd certainly have to deal with quite a bit of distortion if you were hoping for 100% accurate pictures, especially around the edges of vision. With three forming a regular triangle (one at a pole and the other two over the opposite hemisphere) there would be weak visibility at two points on the equator, one on each side. Thus a forth (now two are over each hemisphere) would eliminate those and give you full cover.

It really depends on the technology you're using, how much detail you're hoping to get (probably the most important factor, it could take thousands of sattelites to take high-detail surface imaging of the entire world simultaneously), and what kind of results you're hoping to get. If those factors aren't really important, than I'd say four would work. freshgavin TALK 06:43, 26 January 2006 (UTC)[reply]

In reference to the theoretical rather than the real-world version of the problem, four is the minimum number of points you need to be able to view the whole world from them. Two points opposite each other leave a ring uncovered (since they can't be at infinite distance), and three points in a triangle leave two poles uncovered. But the question asked about satellites, not points in space. A satellite's orbit has to lie in a plane that passes through the center of the Earth, so it's not possible to have 4 satellites maintain a tetrahedral configuration.

There is an easy solution using 6 satellites: just put 3 each in two perpendicular orbits, e.g. an equatorial orbit and a polar orbit, spacing them equally around each orbit. By arranging things more trickily, you can do it with 5. But when this question was asked in the newsgroup rec.puzzles in 1994, Stein Kulseth topped that with this clever solution using 4 satellites in orbits that are nearly, but not quite, circular, and each in a slightly different orbital plane.

For real-world practicality, the 6-satellite solution would probably be best. --Anonymous, 08:10 UTC, January 26, 2006.

The other point to keep in mind is that real spy satellites are, apparently, in polar orbits at relatively low altitudes. --Robert Merkel 08:19, 26 January 2006 (UTC)[reply]

Yea, geosynchronous orbits are at a height of 22,600 miles, at which distance it's difficult to make out much detail. Lower orbits are better, but reduce the field of view, requiring more satellites to cover everything. Also, a view from nearly straight above is desired, as views at sharp angles increase atmospheric interference and increase the number of details hidden behind vertical buildings and walls. So, a whole slew of spy satellites is far better. Also note that some areas demand our attention far more than others, so more satellites in those areas would make sense. We don't need many spy satellites over Easter Island, unless we think some evil supervillain is using it as a base to develop his evil weapon. Hmm, maybe this could be the next James Bond movie ? We could even have the evil supervillain crushed to death by a falling moai (giant statue). :-) StuRat 12:27, 26 January 2006 (UTC)[reply]

That's not how it works; as I understand it, a low polar orbit means that the satellites cover the Earth's surface in "stripes". So one satellite can do the lot if you're prepared to wait a week for your pictures. More satellites mean you get pictures more regularly. Of course, I have no idea precisely how often spy satellites can actually image a particular spot (I did know a guy who used to work for USAF intelligence; he probably knew, but telling me or anyone else would have been a good way to end up in prison for a long time). --Robert Merkel 12:36, 26 January 2006 (UTC)[reply]

Yes, but the question was about how many satellites would be needed to see every spot on Earth simultaneously. That would require a great number, if usable level of detail was needed. StuRat 12:40, 26 January 2006 (UTC)[reply]

I want to get a job where giving away secret information about my corporation can get somebody killed. freshgavin TALK 00:34, 27 January 2006 (UTC)[reply]

Thanks all. --대조 | Talk 13:14, 27 January 2006 (UTC)[reply]

particle accelerators

What would happen if you stood in the path of a high-energy particle accelerator beam (such as the LHC)? Would you feel anything? Would it impact your health? GeorgeStepanek\^talk 09:29, 26 January 2006 (UTC)[reply]

Depends if you were standing at the end just as they took the cover off - you could experience an Alien: Resurrection type of death... (from the hard vacuum). Tzarius 10:48, 26 January 2006 (UTC)[reply]

I'd suppose the question is about the effects of highly accelerated particles hitting your body. I don't think there'd be any noticeable damage or feeling from that. The masses involved are much to small, so at most you'd have a few molecules being disturbed. ☢ Ҡieff⌇↯ 11:17, 26 January 2006 (UTC)[reply]

That's not necessarily true. If a single proton hits you with 1 TeV, the worst it can do is knock out one atom of your DNA. Not much. But what if more than one per second per sq cm hit you? Go here (pdf) and see the beam parameters for LHC. The projected luminosity is apparently about 10^34 protons per square centimeter per second. That's a lot! That's about a trillion moles per second across every square centimeter. Each with 7 TeV. The only saving feature is that the beam is only 16 microns across. Let's put Kieff in there and see what happens :) -lethe ^talk 11:32, 26 January 2006 (UTC)

Sounds fun! :D

But seriously, I don't think you'd feel anything. A few particles wouldn't cause much damage, alright, but a concentration like those would probably cause some direct effect on a cellular level but still, considering the short duration of the "beam" and how narrow it is, I don't believe it'd have a big effect. Regardless, I don't think our nociceptors would be activated by such form of damage at all. ☢ Ҡieff⌇↯ 12:56, 26 January 2006 (UTC)[reply]

They're particles...I wouldn't think it'd make that much difference. It wouldn't be anything like Turok: Dinosaur Hunter where you get stunned and then a splode all over the place...oh, wait, that's a neutron accelerator...mahbad. 12.72.244.198 12:24, 26 January 2006 (UTC)[reply]

Hi everyone, sorry to rain on your speculation, but I believe the answer is that it would kill you. The reason is the existance of particle showers--one proton will cascade into many particles in your body, and many of them will be able to knock out DNA and otherwise do cell damage. When you get hit by all the protons in the ring (on the order of ten trillion I believe, and it would happen almost instantaneously), you're talking a lot of cell damage. I've heard a story, from a fellow physicist, about a professor at a much lower-energy accelerator who got his head in the path of the beam somehow--his brain along the entire path of the beam died from the radiation damage, although he himself survived. -- SCZenz 23:52, 26 January 2006 (UTC)[reply]

Yes, "particle showers" or "collision casscades" will mean a lot more damage than one atom per incedent beam proton. If you ignore nuclear reactions that would occur at that sort of energys the damage would still be huge. the simulation software I have doesn't seem to work at those sorts of energies but at arouns 700MeV a single proton could dislodge over 8000 atoms. In our ion implanter a 9MeV gold beam at high enough currents can heat samples up to the point where they are visably glowing from the energy deposited as heat. --Martyman-(talk) 00:40, 27 January 2006 (UTC)[reply]

Also hospitals use particle accelerators to accelerate protons at humans to destroy innoperable tumors. --Martyman-(talk) 00:42, 27 January 2006 (UTC)[reply]

Thank you for your answers. This is fascinating. So you'd have an immensely powerful but very narrow beam. Or would the "exit wound" be wider? Except the particles are moving so fast, just how much would the cascade be able to spread out? It would make an excellent death ray. GeorgeStepanek\^talk 05:35, 27 January 2006 (UTC)[reply]

My intuition is that I don't think it would spread out very much at all, because there's so much momentum in the direction it's already going, but I think figuring this out exactly is a rather difficult problem. The more I think about it, the more I expect that all the tissue along the beam itself would die, but the effects on the rest of your body might be very limited with proper medical treatment; I'm not sure though. Anyway, the LHC is a lot of effort for a death ray, when bullets work just as well. -- SCZenz 06:43, 27 January 2006 (UTC)[reply]

R4 Gasses

Hello, Can you please help me out & tell me what R4 gasses are, whether they are harmful & where I can find some information about them. They are I believe not used in new applications anymore due to new regulations & (in the U.K.) have to be incinerated at licenced waste disposal facilities. That's all I've been able to find out though. I'd appreciate any information you can give me. Thanks AllanHainey 09:31, 26 January 2006 (UTC)[reply]

You could start at this web page, which says that R4 gases are pyrophoric (that's Greek for 'may blow your head off'). --Heron 23:10, 27 January 2006 (UTC)[reply]

Help With Electronic Chips

I am doing a project which requires me to work with 74ls245, 74l373 and 28c256. I have a problem since I am into computers and not into electronics as such. I would like to have the pin descritions of these chips(not the voltage level...).For eg, whether the pin is active low and some more information. I have tried searching for these but to no avail. I would be glad if you could help. (This question was posted at WP:RD/M but I figured you folks would be better equipped to answer this. 12.72.244.198 12:16, 26 January 2006 (UTC))[reply]

You seem to be looking for datasheets. Searching for 74LS245 datasheet produced, after following a couple of links, this page from Texas Instruments. The PDF file seems to be what you're looking for -- in particular, check the "Function Table" at the top of page 2. You should be able to find similar datasheets for your other ICs. Hope this helps! —David Wahler (talk) 13:49, 26 January 2006 (UTC)[reply]

Chemical smell from pot

(Not that kind of pot...)

I recently bought a cheap stainless steel pot from IKEA, and have noticed that when using it to boil water (practically all I've used it for) it gives off quite a harsh, chemical, metallic smell. I've noticed this before with cheap pots in the past (which is why I usually use my much-loved cast iron and copper...).

What is this, and is it dangerous? — Asbestos | Talk (RFC) 16:59, 26 January 2006 (UTC)[reply]

When I first read this I thought it was the smell of pot (marijuana) which has a somewhat metallic smell. (unsigned comment by User:12.41.204.3)

I don't know exactly. But it could be residues of polishing chemicals and similar, although I assume you did wash the pot before using it. It could be a reaction with the sulphur on the surface of the metal, sulphur tends to make for smelly compounds, even in small amounts. The stainless used for pots needs to be able to be deep drawn, which usually means a higher sulphur content. Whatever it is, I doubt it is dangerous. It'll probably go away as soon as the pot has been burnt in. --BluePlatypus 17:48, 26 January 2006 (UTC)[reply]

I'm not so confidant it's safe. I think you should wash it thoroughly with a detergent then boil water in it until it stops giving off fumes. Don't use the water you boil in it until then, either. Who knows what nasty chemical residue came on the pot. StuRat 17:50, 26 January 2006 (UTC)[reply]

Asbestos, what kind of stove do you use, by the way? Electric or gas? Seeing as it's a metallic smell, it could also be just that: small metal particles left from the polishing. --BluePlatypus 18:39, 26 January 2006 (UTC)[reply]

- I'm using a gas stove. Thanks for the comments above, I'll try giving it a good scrubbing and boiling water for an hour or so. — Asbestos | Talk (RFC) 18:52, 26 January 2006 (UTC)[reply]

- - Well, that explains your preference for copper pans and iron skillets. Gas stoves get (locally) much hotter than electric ones, so if it's some metal-surface reaction going on, that could certainly be a factor. --BluePlatypus 21:50, 26 January 2006 (UTC)[reply]

If you've ever boiled water and 'forgotten' about the pan that could be your culprit. I've burned at least 1 pan that way and it gives off a horrible smell after that, even to the point that it made my eggs smell bad too. I didn't die but I threw the pan away soon after that; it was only about $2. freshgavin TALK 23:44, 26 January 2006 (UTC)[reply]

Radioactivity

Can it be possible to change one stable eliment to another stable eliment by forcing it to undergo radioactivity by bombarding radioactive particles? Or in any possible condition?

Yes. For instance, if you bombard Cobalt-59 (stable) with fast neutrons, neutron capture will occur, forming Cobalt-60 (radioactive) which will eventually decay, emitting a beta particle and giving you stable Nickel-60 as a result. --BluePlatypus 17:18, 26 January 2006 (UTC)[reply]

I think the question is, can it be done without a radioactive intermediary. Actually, I believe it has been done using a nuclear accellerator, back in the days of the cyclotron. They managed to achieve the Alchemists dream of making gold, not out of Lead, but out of Mercury. You did actually specify 'radioactive' particles, so I presume Hydrogen-3 (Tritium) nuclei could be accellerated and made to merge with another elements nuclei, raising the atomic weight by 3 and the number by 1. You would have to choose the element very carefully, but I think Helium-3 would then make Lithium-6, which is stable.

Thank you very much!

Actually, gold has been made from lead (though at a steep price). See Alchemy#Modern 'alchemy'. Superm401 - Talk 07:56, 28 January 2006 (UTC)[reply]

How to avoid the Google idiots

We have a constant problem with computer support here. You give a person a website over the phone or through email. They say it doesn't come up. You test it and it works. After going back and forth, you walk over to the next building and watch them type the URL in Google's search box and hit enter. This isn't a one-time issue. This happens over and over and over. I've even asked people, "Are you typing the address into Google or the address bar?" They say they are typing it into the address bar, but when you check, they are typing it into Google. Is this an anomoly of Google idiots here or is this a problem others have? If it is more common, does anyone have a solution other than remote-desktopping everyone's computer so you can tell them "move your cursor up - no up higher - higher - higher - higher - there. Click on that. THAT is the address bar you idiot!" --Kainaw ^(talk) 19:32, 26 January 2006 (UTC)[reply]

How would that cause problems? Google automatically gives you a link to the URL if you type one in. Are they actually so retarded that they don't follow it before asking for help? Or is there something else happening? Black Carrot 20:00, 26 January 2006 (UTC)[reply]

I am sorry to say so, but yes, they are that retarded. I tried to get permission to put a sticker on top of the monitors that showed a picture of an address bar with a note saying "This is an address bar", but I was told that it made the employees feel dumb. Apparently it is OK for them to be dumb as long as they don't feel dumb. --Kainaw ^(talk) 20:22, 26 January 2006 (UTC)[reply]

The issue there is that some people are stupid, but does that justify treating everyone as stupid ? I get a bit offended when I call a support line and complain that an appliance isn't working, only to have them ask if I've plugged it in. Then again, some may have that exact problem. I also worked on a support line, so think it's best to assume they are intelligent until they prove otherwise. StuRat 08:14, 27 January 2006 (UTC)[reply]

You could try something in reverse. I don't actually think it's reasonable to expect people to know what "Address bar" means. Like "do you see the word Google near the top of the screen by a little box? You need to make sure you don't type in that little box." or even

"do you see the word Google near the top of the screen by a little box? Type the URL in that little box and press Return. What do you see? Good, that part is working. Now you need to type it in the different box, next to the word Address. Try that..." Notinasnaid 21:21, 26 January 2006 (UTC)[reply]

Fight fire with fire. Instead of starting off with "type this address", start off with "search for ______ in google". freshgavin TALK 23:38, 26 January 2006 (UTC)[reply]

Thanks. I think it may work to ask them to use Google first. Then, they can't hide it when I ask if it says Google on the screen. They always say, "No. It didn't say Google anywhere until you came over." --Kainaw ^(talk) 00:47, 27 January 2006 (UTC)[reply]

Hmm, maybe you could just tell them to hit "ALT-D" while the browser is in focus. --Uthbrian (talk) 07:38, 27 January 2006 (UTC)[reply]

Both of my parents do the exact thing you describe, have done so for years, and steadfastly refuse to change their habits because the way they do it is "good enough" for them. (Nor are they willing to learn the meaning of the most basic terms such as "address bar". I haven't even been able to get them to understand that they can have more than one browser window open at the same time; I'm afraid to bring up the concept of tabs.) Short of changing the home page in their browsers to a blank screen (which would probably result in them cutting me out of their will), I don't see what can be done about it. All you can do is figure out some way of phrasing your question so you can at least be able to tell whether your given ~~idiot~~ valued employee is actually using the address bar or not and then ordering them to try the address bar if they haven't already. Perhaps something like, "Do you see the line of icons at the top of the window that say 'Back', 'forward', 'reload', and so on? You do? Goooood. Now see that long white box to the right of it? Goooood. Now take your mouse and point it at the pretty long white box ... No, not the actual mouse in your hand ... just use the mouse to make the arrow on your screen move up to the pretty white box..." --Aaron 08:01, 27 January 2006 (UTC)[reply]

Some people really hate to use the address box because it requires that they type exactly the right thing. One character off and they get nothing, or garbage. A Google search, on the other hand, often pops up a "Do you mean..." prompt if you are at least close to the correct term. Makers of browsers seem to have noticed this and started minimizing the size of the address bar and maximizing the size of the search bar, as a result. They also sometimes have address bar entries that don't find a page automatically go to a search engine. Personally, I think that's a bit much, if I wanted to search, I would have picked "search". So, beware that it may be increasing more difficult for people to avoid doing a search accidentally. StuRat 08:27, 27 January 2006 (UTC)[reply]

If there's one thing Wikipedia has thought me, it's that there's a lot of people who fail to follow instructions even if they're staring right at them. Some people just don't want to do what someone else tells them to do and think their way is better. - Mgm|^(talk) 08:58, 27 January 2006 (UTC)[reply]

A problem is that different browsers look different, also dependent on whether it's the default appearance. Referring to buttons saying 'back' and 'reload' and such wouldn't work in my case, for example. Probably the only thing all address bars have in common is that it's the highest piece of text against a white background in the browser window (then, of course, they'd have to know what a window is, oh dear). Although Opera doesn't have that either (can't remember now how to bring up the address bar in Opera). DirkvdM 10:47, 27 January 2006 (UTC)[reply]

You can also hide the address bar in many browsers, making things even worse. StuRat 12:54, 27 January 2006 (UTC)[reply]

Can you not just change the default page on the company's browsers so that it is either blank or the company's website? Also, can you remove the Google toolbar? Then those who understand how to use an addressbar will also understand how to change the default page back, and those who don't won't be typing addresses into Google. — Asbestos | Talk (RFC) 13:26, 27 January 2006 (UTC)[reply]

When I first started college, I was so computer-illiterate that I tried putting an email address into the website address bar. Now I'm well on my way to complete HTML fluency. If I didn't learn anything else, at least knowing how to use a computer helped. Captain Jackson 15:24, 27 January 2006 (UTC)[reply]

My Spanish teacher last year always used the Google search box as well. At the time, we speculated on what would happen when she found a page they didn't index (thank God I don't live in China). Superm401 - Talk 08:01, 28 January 2006 (UTC)[reply]

doggy medical need devices

i would like to know where i could find pattern or direction for diapers, and any thing that aides a dog,just basic directions that i could adapt for size and need. I have a 17 yr old dog and at times she needs help walking, and use of diapers. i have made other things in the past myself that were cheaper and more comfortable. thankyou

I found this page which has some links that may be useful to you. But, seriously, have you discussed your dog's condition with a vet? While I'm neither a vet nor able to assess your dog's actual condition, I have to wonder - if your dog is so incontinent it needs diapers, and struggles to move, whether another course of action might be in the best interests of the welfare of your dog if rather traumatic for you. I apologise if am misinterpreting your description of your dog's condition. --Robert Merkel 07:26, 27 January 2006 (UTC)[reply]

Population

If one were searching for a recent US census report on the populations of major cities (NY, LA, Houston, etc), where would one look? Black Carrot 20:14, 26 January 2006 (UTC)[reply]

Well, either in my sock-drawer, or at www.census.gov. --BluePlatypus 21:23, 26 January 2006 (UTC)[reply]

The census site is probably the safer of the two places to look. Don't go near the sock-drawer. Grutness...wha? 07:03, 27 January 2006 (UTC)[reply]

Spicy foods & eyesight

After eating a rather spicy Indian meal, I noticed that colours, which normally look a bit flat to me, appeared very bright and vivid, as if turning up the contrast on a TV. Is this a documented phenomenon and/or are there any possible reasons? smurrayinchester^{(User), (Talk)} 20:52, 26 January 2006 (UTC)[reply]

If this was just one particular meal, I would speculate that someone might have slipped something like magic mushrooms into it, since this is exactly the sort of effect that many people report. If it is all meals... a different story. Notinasnaid 21:38, 26 January 2006 (UTC)[reply]

It's always, after all spicy Indian/Chinese/Mexican etc. meals. smurrayinchester^{(User), (Talk)} 21:57, 26 January 2006 (UTC)[reply]

I seem to recall that a few people report psychic effects from monosodium glutamate. Of course it would be pure speculation on my part to suggest that that has anything to do with your observations. It might be more fun not to find out; what if people told you you were imagining it, and you believed them, and it went away? --Trovatore 22:04, 26 January 2006 (UTC)[reply]

Interesting. I remember reading somewhere (but I don't remember where) that your vision actually decreases after eating a large meal. Cybergoth 22:12, 26 January 2006 (UTC)[reply]

Are any other senses affected, or just your sight? It's also possible that it might just be waking you up and feel less dull in general. Night Gyr 22:20, 26 January 2006 (UTC)[reply]

Just sight. It seems to be to do with spiciness (eating a korma has nowhere near the same effect as a jalfrezi and madras). smurrayinchester^{(User), (Talk)} 22:33, 26 January 2006 (UTC)[reply]

I remember reading something about being able to see into the future after eating too much spice. --BluePlatypus 23:27, 26 January 2006 (UTC)[reply]

Maybe it's some form of synaesthesia? —Keenan Pepper 23:38, 26 January 2006 (UTC)[reply]

It would be neat to test this scientifically. We could come up with something similar to tests for color-blindness, a series of dots with only a subtle color difference, that, if detected, allows you to see a hidden picture. If you couldn't make out the pic normally, but could after eating spicy foods, that would be proof that it works. Even more exciting would be if nobody else could see the pic, but only you could after eating the spice. This would prove it's not just a perception issue, but that your eyesight really was enhanced over a normal person's eyesight. If that was the case, isolating the chemical(s) causing this effect would be the next step, leading to a new nutritional supplement. StuRat 08:00, 27 January 2006 (UTC)[reply]

See Curry#Curry_addiction. Maybe that's why I like curry powder in my spinach. DirkvdM 10:54, 27 January 2006 (UTC)[reply]

methonal water mix

was just wondering if anyone had heard if there was any type of reaction when water and methonal were mixed and then put into a Aluminum tank. We ran into a problem with it eating away at the aluminum.

There's no such thing as "methonal", and methanol wouldn't react with aluminum, as far as I know. —Keenan Pepper 23:19, 26 January 2006 (UTC)[reply]

Nope. The pKa of methanol is 15.2, which means that it's far too weak an acid to do something. Neither water, methanol or a mixture of them should have any effect on aluminium. I'd say it would have to be something else. --BluePlatypus 23:24, 26 January 2006 (UTC)[reply]

On the other hand, this MSDS says "Do not store in aluminum or lead containers.". I wonder why that is? —Keenan Pepper 23:40, 26 January 2006 (UTC)[reply]

Actually, I'm finding a lot of sites that say methanol is corrosive to aluminum. Maybe it does something to the protective oxide layer? —Keenan Pepper 23:49, 26 January 2006 (UTC)[reply]

Yeah, on the other hand, that is very possible. Naked aluminium is quite reactive. If the oxide layer is too thin, or damaged, then the methanol could probably eat away at it quickly. --BluePlatypus 00:00, 27 January 2006 (UTC)[reply]

Methanol can definitely corrode some metals, which can be a pain when running a car on the stuff. My chemistry text book has image of some rods from a methanol engine covered in holes and damage. It might be methanol acting as a solvent or forming methanoic acid. It could also be removing the layer of Aluminium oxide from the aluminium, damaging it that way. smurrayinchester^{(User), (Talk)} 10:48, 27 January 2006 (UTC)[reply]

Yes, methanol is corrosive to aluminium, magnesium and lead. The main distinction with water is that the methoxides are soluble in methanol, whereas aluminium oxide is insoluble in water: hence, as soon as corrosion gets started, it continues. Physchim62 (talk) 13:24, 27 January 2006 (UTC)[reply]

Cool, that makes sense. I'll add it to the Methanol article. —Keenan Pepper 16:47, 27 January 2006 (UTC)[reply]

January 27

Speaking of GSO, space elevator

Assuming it's gonna be built (a pretty big assumption I'd say) and they decide to build the hub station on land instead of water (another rather large assumption) what (equatorial) country do you think it would be based in? Let's put the time at +50 years from now. I'd vote for Brazil, though it would be in less-than-perfect area in the north away from the Metropolitan centers. freshgavin TALK 00:07, 27 January 2006 (UTC)[reply]

Brad Edwards's NIAC study suggests that Ecuador or Tanzania would be good locations if a land-based anchor was chosen. --Robert Merkel 00:25, 27 January 2006 (UTC)[reply]

They make some good points, although it seems they're aiming for international waters, and it's not really a land-based anchor! freshgavin TALK 03:34, 27 January 2006 (UTC)[reply]

Why would you put a space elevator at the Equator? Wouldn't the most obvious place be the North or south pole? That way it would be in generally the same spot.

A space elevator has one end attached to the ground (so it is in "generally the same spot") and rises upward to geostationary orbit and beyond. Geostationary orbit is over the equator. Or in the Earth's rotating reference frame, the space elevator is held up by centrifugal force, which is directly upward only at the equator. The thing cannot exist anywhere else. Further, there are asymmetries in the Earth that make some points on the equator are better than others, but I forget the details. --Anonymous, 06:20 UTC, January 27.

At the equator, objects traveling up the elevator will gain the greatest kinetic energy possible by that method, and can easily be placed in geosynchronous orbit. The elevator can also be stabilized with a counterweight in orbit. Achieving a stable polar orbit would be highly impractical. ‣ᓛᖁ

ᑐ 04:54, 27 January 2006 (UTC)[reply]

Though I'd like to try it just for fun! Screw escape velocity. freshgavin TALK 05:46, 27 January 2006 (UTC)[reply]

The kinetic energy reason is also why space agencies launch from as close to the equater as possible (The US launches from the far south, Russia launches from Central Asia, and Europe uses French Guiana). Given that - of those three - French Guana is the closest to the equator (5° N) and already has the technical equipment for space industry close-by. Other viable possibilities would be Gabon, Kenya, Malaysia and Indonesia, although the earthquake-prone nature of the latter makes it more problematic. Grutness...wha? 07:09, 27 January 2006 (UTC)[reply]

I'm not convinced of the feasibility of a space elevator. Finding materials which can withstand the forces would be quite an issue. Assuming they are found, and the elevator shaft can be built for a mere million dollars per kilometer, at a height of 35,786 km that would still be 36 trillion dollars, which nobody seems to have just lying around. If a world effort was made to build it (over decades), then some political method would be needed to assure access to it by the contributors. This would be similar to issues with the Suez and Panama canals. Nobody would be willing to contribute that much money without knowing they have permanent access to the result. Perhaps an "international zone", similar to Antarctica, could be established around the base to prevent the surrounding country from having veto power over who can use it. StuRat 07:35, 27 January 2006 (UTC)[reply]

Pretty much all equatorial countries are politically unstable. Maybe the Maldives would be willing to give away part of their southern territory on exchange for a rescue plan for their islands (which are going to be swamped by a rising sea). Geologically most stable would be in the Pacific (the biggest plate), but the remoteness might be a problem with construction (getting building material and other resources in) and usage (if it's going to be used for space tourism you'd want population and transportation centres nearby). DirkvdM 11:04, 27 January 2006 (UTC)[reply]

Of course, if you're going to build a 35,786 km tall elevator, it wouldn't be much of an addition to build it a km or two longer and place it on the sea floor. StuRat 12:45, 27 January 2006 (UTC)[reply]

In which case the elevator could also have a 'basement' level and we would have a choice between going into space or to the sea floor. DirkvdM 13:18, 28 January 2006 (UTC)[reply]

Building it to the sea floor is an interesting idea but would definitely increase the engineering complexity. Remember that the pressure difference for every 10 m (33 feet) of ocean depth is equivalent to the entire difference between air pressure at sea level and outer space. Also, underwater structures are a helluvalot harder to access for routine maintenance than those on dry land. Further, as a political solution it could backfire: there might be more countries willing to try to seize the tower by force if there's no country that owns it. --Anonymous, 20:30 UTC, January 28.

failing that, some Pacific nations (like Tuvalu) are in a similar fix to the Maldives. Grutness...wha? 22:37, 27 January 2006 (UTC)[reply]

StuRat, have a look at Brad Edwards' proposal. He makes a reasonably convincing case that if carbon nanotubes composites of sufficient strength become available (which I fully agree is a big "if") that a useful space elevator can be constructed for a cost of less than $10 billion dollars. Chicken feed compared to, say, missile defence, the F-22, or ethanol-related pork barelling. --Robert Merkel 09:22, 28 January 2006 (UTC)[reply]

Nuclear energy to treat disease

Hello, my name's Kate. I have been searching through the net for a few hours now, possibly more, and can not find much information on how nuclear energy is used to treat diseases. I pretty much understand the side effects, as well as the benifits as well, but i dont really understand how it actually works and how it is used. Could you please help me? Thank You. Kate.

There's an article on Nuclear_medicine concerning radiopharmaceuticals. freshgavin TALK 00:21, 27 January 2006 (UTC)[reply]

Radiation is also used for diagnostic purposes in medicine, in things like PET scanners, NMR and Radium is used in some cancer therapies. Radon therapy is also a more left-field treatment still in use. Grutness...wha? 07:17, 27 January 2006 (UTC)[reply]

There is one example I remember that helped me to understand how nuclear energy could be used to treat disease (hopefully it's simple yet accurate, I'm sure someone will correct me if I'm wrong). It is the use of iodine to treat thyroid cancer. The thyroid (in your neck) concentrates any iodine in your body. So, if you absorb some iodine a fair amount will go to the thyroid. If you have thyroid cancer, you can take some radioactive iodine, a lot of which will end up in your thyroid. Although the radioactive iodine will kill many good cells, since it concentrates in the same place as the cancer cells, hopefully many cancer cells will die - and you will live.--Commander Keane 19:30, 27 January 2006 (UTC)[reply]

That's correct, and recently metastasized thyroid cancer cells throughout the body also have an affinity for iodine, so will absorb the radioactive iodine and be destroyed, as well. Of course, all this completely destroys the thyroid, so thyroid replacement therapy is needed, say by taking Synthroid for the rest of your life. Not a bad tradeoff for curing cancer. StuRat 20:58, 27 January 2006 (UTC)[reply]

Darrieus wind turbines

I was just reading about Darrieus wind turbines and I was somewhat confused by the airfoil diagrams in the article; These diagrams show the lift vector on the airfoil as having a forward component. When I learned aerodynamics I was taught that the lift vector always had a rearwards component and that this is what creates induced drag. So, is there something I'm missing? How is it possible to have an airfoil with a forward-leaning lift vector? -User:Lommer | ^talk 00:20, 27 January 2006 (UTC)[reply]

Are you saying the horizontal component (horizontal as in the illustration) of the lift vector should be reversed, or the entire vector? It's been a while since I took turbomachines, but I might give it a try. deeptrivia (talk) 03:21, 27 January 2006 (UTC)[reply]

You're almost right, Lommer - except that the lift vector on an aerofoil points slightly more 'backwards' (due to induced drag) than the 'ideal' lift vector (which is always perpendicular to the incoming flow). This is going to be somewhat tricky to explain in words, but I'll try.

Take a look at this aerofoil diagram. To translate this to our windmill case, V_inf is red arrow on the windmill picture. The ideal lift vector is the one indicated in green on that same drawing - it's always perpendicular to the incoming flow. However, the aerofoil, by creating lift also creates downwash (also see induced drag), which alters the direction of the incoming flow by adding to it a component parallel to the 'ideal' lift (labelled V^ind on the aerofoil diagram). This has the effect of altering the 'effective' (as seen from the aerofoil's perspective) angle of attack, which tilts the lift vector 'backwards' (see the arrow labelled Normal Force F on the aerofoil diagram - it's perpendicular to the 'effective' incoming flow). Now, back to the windmill diagram: Change the direction of the incoming flow (red arrow) by adding a component parallel and opposite to the green arrow. This reduces the angle of attack and tilts the lift vector backwards. However, because the angle of attack of this aerofoil is so great, it doesn't tilt the 'new' lift vector back beyond the vertical (towards the centre pivot), therefore, the lift still provides a component in the left direction, turning the windmill.

So, in a way, you were right - induced drag means that the lift vector must always point more 'backwards' than the ideal lift vector (creating a drag component). However, it must always point more backwards than the ideal lift vector which is perpendicular to the incoming flow - hence, for a situation like this, with a large angle of attack, the lift vector can point "forward" with respect to the aerofoil geometry.

I hope that made sense :) — QuantumEleven | (talk) 10:38, 27 January 2006 (UTC)[reply]

https

The following discussion is an archived debate of a problem I was having with my firewall

Please do not modify it, unless of course you want to.

The result of the debate was DISABLE NORTONS' Built in Firewall--Aolanon... 03:20, 27 January 2006 (UTC)[reply]

For some odd reason, every single time I try to log into anything, I get a "page cannot be displayed" message, happens with anything that requries a .cgi script, seems to keep me from logging into any type of mail server, in this case yahoo, at first I thought their server might be down, but it's been a few days... still nothing The only thing I can think of, is that this is a brand new computer, and it's possible there's some security setting that's causing this????--Aolanon... 00:23, 27 January 2006 (UTC)[reply]

There could be a range of problems here, and the first step to solving it is to get all the details. How exactly are you connected to the internet? If you are connected exactly the same way on your new computer as on your old computer (by ethernet cable, maybe?), one possibility is that your TCP/IP settings have not been transferred to the new computer. If you're using Windows, do an ipconfig in command prompt on both the old computer and the new computer, and see if the results are the same or different. More details about your connection type and operating system would be appreciated. -- Daverocks (talk) 01:28, 27 January 2006 (UTC)[reply]

Windows XP Home Edition, both computers, currently using a linksys router to connect to a broadband connection, and my old computer was buggy enough that I never even bothered with file/settings transfer from the old machine, to the new, so there's really no basis for comparison--Aolanon... 02:09, 27 January 2006 (UTC)[reply]

A little bit more information, this only seems to happen when a form takes me from a secure, to unsecure internet connection, as in http to https--Aolanon... 02:09, 27 January 2006 (UTC)[reply]

Ok, I think I've confirmed it, the problem seems to be that I can't load any https pages at all, the only thing I can't figure out is why it's doing this all of a sudden--Aolanon... 02:34, 27 January 2006 (UTC)[reply]

Have you been playing with the firewall settings on your computer or router? HTTPS uses a different port to HTTP(80). --Martyman-(talk) 02:41, 27 January 2006 (UTC)[reply]

I think that's it actually, the newer computer came prebundled with Norton Security Center, which seems to have taken on a life of it's own, now that I look at it, it's somehow turned it's own firewall back on, even though I had it disabled, and now it doesn't want to shut off--Aolanon... 02:56, 27 January 2006 (UTC)[reply]

No, wait, this is driving me nuts, I just checked again, and despite Norton's quirky behavior, I don't think that's it either, according to Norton, ports 80, 81, and 82 are not blocked, so that shouldn't be causing this problem then--Aolanon... 03:00, 27 January 2006 (UTC)[reply]

Problem solved, it was Norton after all... It took a bit of doing but I got it to back down, and now everything works again.. or at least it's close enough--Aolanon... 03:11, 27 January 2006 (UTC)[reply]

The above discussion is preserved as an archive of this reference desk question. Please do modify it, as much as you like.

diesel Generating Sets

Is it possible to adjust the frequency of diesel Generating sets. --61.0.135.181 01:21, 27 January 2006 (UTC)[reply]

Theoretically, yes. You can even buy some diesel gensets that are switchable between 50 and 60 Hz output (for instance, this Chinese company sells one. But as to whether this is possible, or easy, with your particular genset is another question entirely. --Robert Merkel 07:07, 27 January 2006 (UTC)[reply]

Is the sugar important in the fermentation process of making vinegar??? How?

Greetings!

I am asking the question: "Is the sugar important in the fermentation process of making vinegar??? How?" because we need more information of the function of the sugar in the fermentation process of making vinegar for my group's investigatory project... We have to prove to others that sugar aside from yeast also influences the fast decreasing of the pH value in making vinegar...

Please help me!!!

Your efforts will be very much appreciated... If ever you have useful references for the answer we need, please post them too... Thank you!!!

                                                      Daren

Of course! Sugar is the main ingredient. It's the sugar that's getting fermented. See fermentation, vinegar, Acetic_acid#Fermentation, etc.deeptrivia (talk) 03:11, 27 January 2006 (UTC)[reply]

Problems reading pictures from CD

I burned some pics on a cd in 2002. Now I can't open the pics. It says that a plug-in is missing or the files are corrupt. When I burnt the cd i could open the pics (on my old pc) even from the cd. What's going wrong and how can I recover the pictures? Thanks! deeptrivia (talk) 03:09, 27 January 2006 (UTC)[reply]

Without more information the only thing I can assume is that the CD is damaged (scratched, warped by heat, etc.) and your CD drive is having trouble reading the header of the CD (the part at the beginning where it gives information about the rest of the CD).

It may also be that the pictures are in an old format that your PC doesn't recognize, but I can't tell without more information : ). freshgavin TALK 03:30, 27 January 2006 (UTC)[reply]

Thanks! Assuming a part of the CD, like the header, is damaged, what ways of data recovery exist? What more information would be helpful? deeptrivia (talk) 03:41, 27 January 2006 (UTC)[reply]

By the way, it shows all the files and their correct sizes. But when I open them, it says they are corrupt. deeptrivia (talk) 04:00, 27 January 2006 (UTC)[reply]

What kind of files are they? (What is the file extention?) freshgavin TALK 04:04, 27 January 2006 (UTC)[reply]

They are all JPG files. deeptrivia (talk) 04:04, 27 January 2006 (UTC)[reply]

Hmm, it's a little bit odd that it shows the file info correctly but won't display the images. If there's no visual damage to the CD (obviously look for scratches or strange coloring on the data side) then there's a few other possible reasons. Some types of blank CDs don't work so well in some types of CD readers (problems generally come from cheap CDs and cheap CD readers) so you could try it on someone elses computer. freshgavin TALK 04:28, 27 January 2006 (UTC)[reply]

Agreed, try a different CD player. Specifically, be sure you are using a CD-only reader. Combo CD/DVD readers sometimes make compromises to support both formats that can cause reading errors. StuRat 07:05, 27 January 2006 (UTC)[reply]

I can't say if this will definitely work, but you can try Isobuster. --Uthbrian (talk) 07:19, 27 January 2006 (UTC)[reply]

This does not sound like a broken CD. The message doesn't suggest that at all. "Missing plug-in" is all about software. Make sure you are trying to open the JPEG files in a suitable program. DON'T just double click on them. Notinasnaid 09:08, 27 January 2006 (UTC)[reply]

Try to find a copy of the program you saved them with -- it may have idiosyncracies in its format that show up as corruption to whatever you're using now. Night Gyr 12:08, 27 January 2006 (UTC)[reply]

Thanks for all your messages. The CD is not damaged, i think. There are abt 10 folders on it, just one doenst work. I burnt three sessions on it (almost all photos). The folder i burnt on the last session, doesnt work. I tried to upload one of the pics on wikipedia, to give an idea of the kind of corruption it might be, but it doesn't upload it, giving the error: "The file is corrupt or has an incorrect extension. Please check the file and upload again." What can I do? deeptrivia (talk) 15:00, 27 January 2006 (UTC)[reply]

Could you upload a sample onto a public webspace somewhere? Tripod will give you 20MB quick. enochlau (talk) 17:26, 27 January 2006 (UTC)[reply]

Here is a sample picture. Could you suggest a good software to recover as much as possible from corrupted JPGs, or some other means to rescue these pictures? Thanks!

Okie dokes. I couldn't get it to open, and I think I have evidence that your CD is borked. I opened up the file in a hex editor, and the JPEG magic number that I found at the start of all my good JPEG files was found in the middle of the file, so the CD is probably indicating where the files start/end wrong. Also, large sections of the file were the same character, which is unusual for a JPEG file, since it's not a bitmap - further suggestions that it's corrupted. :( enochlau (talk) 22:38, 27 January 2006 (UTC)[reply]

The file is OK except that it has 4096 bytes of garbage in front of it and presumably an equal amount of data missing from the end. I've uploaded the image without the first 4kb here. This suggests that enochlau's guess about the start/end offsets on the CD is probably correct. There are programs that can recover JPEG files from corrupted or accidentally formatted disks by scanning for the magic numbers — you may want to try one of them. Those programs usually can't handle fragmented files, but since CDs are normally never fragmented you should have no such problems in this case. —Ilmari Karonen (talk) 23:51, 27 January 2006 (UTC)[reply]

Thanks a ton Ilmari and enochlau! You guys rock!! Could you tell me how did you fix this file, and how can I do the same? Can you suggest a good program which does this thing automatically? deeptrivia (talk) 01:55, 28 January 2006 (UTC)[reply]

See User_talk:Ilmari_Karonen#The_corrupted_JPEG_file. enochlau (talk) 06:19, 28 January 2006 (UTC)[reply]

Human ancestry tree

Are all the Hominids (? ) ( neanderthals, erectus, and all) HUMANS? I mean, they aren't modern humans because they aren't homo sapiens, but can they be called Human? or just hominid?.--Cosmic girl 04:07, 27 January 2006 (UTC)[reply]

Not being a native English speaker, you may not know that "homos" is also an insulting slang term for homosexuals. Your meaning here was quite clear, but I just wanted to point that out so you don't get in trouble using the term elsewhere. For example, calling a group of men "homos" instead of "people" would be a very bad thing. StuRat 06:58, 27 January 2006 (UTC)[reply]

I didn't know that! I'm sorry...this is embarassing, but thank you for telling me! I already fixed the question,I hope it's understandable.--Cosmic girl 16:14, 27 January 2006 (UTC)[reply]

No problem, glad I could teach you a bit of English slang. StuRat 20:42, 27 January 2006 (UTC)[reply]

According to Homo (genus), even Neanderthal should not be called part of the Homo sapiens (human) species. But Neanderthal makes the point that some people suspect that humans and Neanderthal could interbreed. --JWSchmidt 04:21, 27 January 2006 (UTC)[reply]

They're probably best called hominids, since human really refers to a specific species. The distinction isn't very large, though, and if we're going to name the genus "same as us", we might as well call the other species "human" too. I think the main reason for using "hominid" instead is the tendency for people to want special status above animals. ‣ᓛᖁ

ᑐ 04:24, 27 January 2006 (UTC)[reply]

Agreed. How close to us a species needs to be to be considered "human" is just a matter of opinion. StuRat 06:45, 27 January 2006 (UTC)[reply]

Nitpick: The genus name Homo is not from the Greek homos meaning "same", it's from the Latin homo, homin- meaning "man". —Keenan Pepper 06:33, 27 January 2006 (UTC)[reply]

A somewhat finer picking: My Dutch 'foreign words' dictionary says that 'homo-' (as a prefix) indeed stems from Greek for 'same' and that 'homo' (as a word) is Latin for human and is related to the word 'humus', for 'earth' (in the sense of ground, soil). DirkvdM 11:25, 27 January 2006 (UTC)[reply]

I'm half Neanderthal (my father was one), and I get very upset when people try to suggest that I'm not a human. -lethe ^talk 06:48, 27 January 2006 (UTC)

Are you serious Lethe? or is that a joke? I thought Neanderthals where extinct long ago.--Cosmic girl 16:17, 27 January 2006 (UTC)[reply]

Yes, that's a joke, LOL. StuRat 20:32, 27 January 2006 (UTC)[reply]

The term "human", in common usage, refers specifically to Homo sapiens. However, broadly speaking, it may also refer to any members of the genus Homo. See [12] (click on second definition, "noun"). Or for instance, when Homo floresiensis was discovered, Scientific American called it "The Littlest Human" on its cover. You will often find "modern humans" or "anatomically modern humans" written in texts dealing with human evolution to differentiate us from our close ancestors. — Knowledge Seeker দ 07:05, 27 January 2006 (UTC)[reply]

Another nitpick. The name hominid properly refers to a species in the family Hominidae, which is generally considered to include humans and the great apes — gorillas, chimpanzees and orangutans. Unfortunately there isn't a widely-understood scientific term meaning "modern humans and other hominids more closely related to humans than chimpanzees". In some classifications this group is classified as the subtribe Hominina, so you could try using the term homininan. But few people will understand what you mean. Gdr 12:23, 27 January 2006 (UTC)[reply]

I asked this because I read the article about Homo Floresiensis and I also read the article in New Scientist and saw that they where called 'humans' so wondered, since what stage in evolution can some ape or great ape be considered human?. --Cosmic girl 16:20, 27 January 2006 (UTC)[reply]

Well, the term "human" is a bit vague. If you mean the same species as us, which is defined as being able to breed with us and produce fertile offspring, then apes are definitely out, but Neanderthals and Homo Floresiensis might be included. Also note that apes are not direct ancestors of humans, as anti-science religious zealots always say is claimed by Evolution. All of our ancestors are extinct. The nearest common descendent isn't even the apes, but rather chimpanzees/bonobos with 98% genetic material in common with us. StuRat 20:32, 27 January 2006 (UTC)[reply]

But chimpanzees are apes! (And so, at least biologically, are humans.) Gdr 22:06, 27 January 2006 (UTC)[reply]

Which suggests that all humans are apes, but not all apes are humans. JackofOz 22:39, 27 January 2006 (UTC)[reply]

Right, we're not descendants of apes, we are apes. A common misconception, not just among religious zealots. DirkvdM 13:30, 28 January 2006 (UTC)[reply]

Thank you guys, I understand :D --Cosmic girl 03:40, 28 January 2006 (UTC)[reply]

scratching an itch

How do you scratch an itch in side a spacesute? Say like your nose or the bottom of your foot? I have saked this question several time but no answer.

I've heard that they actually have something inside the helmet for that purpose (and I assume it serves some other useful purpose too), like a small protrusion that you can touch to your face by looking down, but as for scratching the bottom of your foot ... we have enough trouble trying to itch down there standing on Earth! freshgavin TALK 05:43, 27 January 2006 (UTC)[reply]

Related question: what does a concert pianist do when he itches? I've had this problem, wanting to scratch but not wanting to stop playing. And then realised that that would be hell if I were to ever perform before an audience. Irrespective of where the itch is, although that can make it even worse (some spots one does not scratch in public). DirkvdM 11:29, 27 January 2006 (UTC)[reply]

Just switch to one of those pieces for one-handed pianists until you're done scratching, LOL. But seriously, if that was a problem on a regular basis you might want to liberally apply a lotion containing menthol-eucalyptus right before the concert, that should both relieve dry skin and act as a topical anesthetic to prevent itching. Also, avoid itchy clothes like wool. If the itching persists, it may have a psychological basis (a manifestation of anxiety ?). StuRat 12:25, 27 January 2006 (UTC)[reply]

Well, it's hardly ever a problem, it's just that when it happens it's really annoying. But then, during a concert, the anxiety thing might kick in. Especially now that you've pointed that out to me, it is sure to worry me, and therefore happen, whenever I give a concert. Thanks a lot! luckily, I'm not a concert pianist. By the way, I only know of one piano piece for one hand, by Ravel. Are there any more? The one by Ravel is said to be almost impossible to play, so there can't be a big 'market' for it. DirkvdM 16:07, 27 January 2006 (UTC)[reply]

"Twinkle, twinkle, little star". You can play that with one finger, LOL. StuRat 20:25, 27 January 2006 (UTC)[reply]

There are lots of pieces for one hand, but they get little commercial notice. Most of them are for left hand, but there are some for right hand too. I have a volume (edited by Raymond Lewenthal) of one-handed pieces by such composers as Alkan, Bartok, Blumenfeld, Godowsky, Liszt, Moszkowski, Reger, Saint-Saens, and Scriabin. It also includes pieces arranged by others for one hand piano, eg. Godowsky arranged Chopin's Etude in E flat minor, Op.10/6, for left hand. Sounds impossible, but that was chicken feed for Leopold. Also see [13] for a discussion of the history and repertoire of music for piano one-hand. Enjoy. JackofOz 22:36, 27 January 2006 (UTC)[reply]

BTW, what's the Ravel piece, Dirk? I don't think I've ever heard of it. JackofOz 05:23, 28 January 2006 (UTC)[reply]

Piano Concerto for the Left Hand (Ravel). See that little box at the left top of this page, where it says 'search'...? :) DirkvdM 13:43, 28 January 2006 (UTC)[reply]

Of course! I thought you were talking about pieces for piano solo (that's what "piano piece" normally means). Nothing is considered 'impossible' these days, just 'challenging'. The Ravel is in the repertoire of a large number of pianists and has had umpteen recordings. Prokofiev, Richard Strauss, Korngold, and others all wrote concertos for left hand too. :-) JackofOz 14:04, 28 January 2006 (UTC)[reply]

I guess the same question could apply to any performance artist. The answer would be that they are far too involved in what they are doing to be bothered by an itch. This reminds me of the little boy being taught about birth, who was desperate to know what would happen if the woman wanted a pee while she was having a baby. --Shantavira 16:00, 27 January 2006 (UTC)[reply]

And since a sneeze gives an almost orgasmic feeling, I once wondered what would happen if one would sneeze during an orgasm, but I suppose that is not very likely either. Same for a good crap, but that's even less likely. :) DirkvdM 16:07, 27 January 2006 (UTC)[reply]

Ewwww ! Either you enjoy defecating way too much or sex way too little, to think they are equivalent, LOL. StuRat 20:19, 27 January 2006 (UTC)[reply]

See Blumpkin Night Gyr 02:18, 28 January 2006 (UTC)[reply]

Oh dear me, I've gotten used to others already having come up with weird ideas of mine, but I certainly didn't expect that to be the case here. Turns out there are others as weird as me. That's scary. DirkvdM 13:43, 28 January 2006 (UTC)[reply]

white blood cells

Very interesting facts about white blood cells. I was just wondering where white blood cells come from ?

It depends on their production. They most commonly come from either the bone marrow or the thymus, hence the names B cells and T cells. Elle _{vécut heureuse} ^{à jamais} (Be eudaimonic!) 05:26, 27 January 2006 (UTC)[reply]

B and T cells are only a subset of the WBCs in the body. There are other WBCs, including monocytes, neutrophils, and eosinophils. Where they come from depends on how far back you care to look; the most recent ancestors of the WBCs would be the uni- and bipotential stem cells (i.e. CFC-G, CFC-GM, CFC-M, and CFC-EO).

Where blood cells (including WBCs) are formed changes throughout life. WBCs aren't produced until the second fetal month, when they are generated in the liver, spleen, and thymus (during the so-called hepatosplenothymic phase). Later, this shifts to the bone marrow and lymphoid tissue (e.g. spleen, thymus, lymph nodes), where it continues into adulthood. Hope that helps, David Iberri (talk) 06:39, 27 January 2006 (UTC)[reply]

though probably the notion that T cells come from the thymus needs correction. "T cells" (in the adult) originate in the bone marrow. They mature in, but don't originate in, the thymus. Under normal circumstance, there shouldn't be any blood-cell production in the adult liver, spleen, or lymph nodes. - Nunh-huh 22:48, 27 January 2006 (UTC)[reply]

Good point about T cells, which again points to the "how far back you want to look" idea. Regarding extramedullary hematopoiesis, it's my understanding that minimal (i.e. negligible) hematopoiesis occurs in lymphoid tissue even in healthy adults. Also, to nitpick an earlier post, the B in B cell isn't for bone marrow; it's for bursa of Fabricius. --David Iberri (talk) 05:06, 28 January 2006 (UTC)[reply]

CV21 - who owns it ?

does anyone know about www.cv21.co.uk......is it a secret advertising/design agency?

i have tryed to contact them but they do not reply.... as i have heard they work for free if you are the right client...

please advise as i would like to know if anyone has had any luck contacting them.

regards

Mr Hall (OBE)

Your question was answered here. User:AlMac|^(talk) 11:49, 27 January 2006 (UTC)[reply]

Please do not post your questions more than once. We may not know the answer to your question, are still figuring it out, or are refusing to answer for one of the reasons stated at the top of this page. Asking us a second time will not likely get you your answer either, and almost guarantees you we will be ignoring you in the future. Your question may be deleted if you see this notice; you should reformat it to prevent this from happening.

As several people have posted other places that you have posted this question, we have no idea what you are referring to? Who owns it depends on what "it" is. You know a lot more about "it" than anyone who can help advise you. User:AlMac|^(talk) 10:03, 27 January 2006 (UTC)[reply]

Water as a fuel

Hi, I read in my sceince text book that it can be possible to use water as a fuel for the cars in near future. Hydrogen and Oxygen is diffused by electrolysis and the produced Hydrogen is combusted for producing energy.After combustion the Hydrogen gets oxydized and again forms water. But there are some problems like its difficult to control the combustion of Hydrogen because its like a blast. and because after combustion it form water in exhaust making it wet and electrolysis of water on large scale to produce enough energy to drive a car. But would it be possible to do this? If yes then it would be very revolutionary step in the world of science. Any explaination would be thankful. --Manasmdk 10:54, 27 January 2006 (UTC)manasmdk[reply]

See our article on Hydrogen economy, which gives a quite detailed overview of the concept. Note that hydrogen could not serve as a fuel in the sense of directly providing energy (since the whole system would still need energy input for electrolysis), only as a means of transporting/distributing energy after electrolysis has occured at some convenient place -- Ferkelparade π 11:02, 27 January 2006 (UTC)[reply]

Hydrogen explosions are not difficult to control. Internal combustion engines use explosions all the time. There's also no problem with forming water in exhaust - bear in mind other fuels - gasoline, etc. produce water during combustion as well, as they are carbohydrates...in fact most of the energy in these fuels come from the release of protons (hydrogen) and high energy electrons which had been earlier stored in organic material for decades...when combined with a highly electronegative element like oxygen, energy is produced. Hydrogen doesn't have the high energy bond, but it still remains the primary source of energy in a fuel...so pure hydrogen is a fuel in itself. The problem is in its density - organic molecules tend to have more mass over less space because of intermolecular forces as well as sharing of electron orbital pairs, thereby making lots of fuels a liquid (including ethanol and gasoline)...for example propane or methane are less so (which is why it isn't often an automobile fuel). The difference is that gasoline might contain many impurities and pollutants, nitrites, sulfides, sulphates, etc. making it impure, when hydrogen would have no such mixtures. This is because organic matter such as plants extract minerals from the soil during their life, incorporate sulfur and nitrogen into their amino acids - when the proteins (made up of amino acids) decompose, the sulfur and the nitrogen in them breaks off and forms new compounds in the organic matter and become pollutants when burnt (forming nitrogen oxide, sulfur oxide, etc.. Elle _{vécut heureuse} ^{à jamais} (Be eudaimonic!) 11:09, 27 January 2006 (UTC)[reply]

Storing hydrogen is difficult because as a gas it takes up so much room, and it has to be very cold and/or under a lot of pressure to make it a liquid, either of which are dangerous in a car. Internal combustion engines are also quite inefficient due to all the heat energy that is wasted and due to the weight of the engine and other heavy components. Fuel cells have the potential to provide for more efficient combustion of hydrogen and oxygen. One last problem to overcome is the lack of places to fuel up with hydrogen. If there aren't sufficient gas stations, the hydrolysis of water to produce hydrogen could be done in your home, using electricity. Instead of just releasing the oxygen produced, it could be used to increase the efficiency of natural gas burned in the furnace, water heater, and gas stove. This would be especially good if the combustion could be made efficient enough to allow venting of the gases inside the home, which is normally only done for gas stoves. This is due to the toxicity of unburned and partially burned gas and the removal of oxygen from the air, which can eventually lead to the formation of deadly carbon monoxide. The water vapor would still be a problem, however, condensing on windows and cold plumbing fixtures. Perhaps a dehumidifier would be needed. StuRat 12:10, 27 January 2006 (UTC)[reply]

One other problem with storing hydrogen is the para/ortho problem. When very cold the ortho converts slowly to para and releases energy, heating up the liquid and eventually causing a container breach. There are catalysts which can convert the ortho to para prior to liquifying.

Lithium hydride storage devices have shown promise for storing hydrogen. This would avoid the problems involved in storing hydrogen in high pressure containers. The biggest problem with this whole concept is that it takes energy to electroylse water, lots of energy. So far this comes largely from fossil fuels, so a hydrogen economy would not do much to reduce our fossil fuel consumption.

Yes, a new round of nuclear reactors, this time deep in mines far from populated areas, is needed to replace the aging surface reactors placed near populated areas right now. People will not, and should not, accept the level of risk (especially in this modern age of terrorism) associated with these surface reactors. StuRat 14:46, 27 January 2006 (UTC)[reply]

Hydrogen gas can also be very dangerous, too. The most infamous example would be the Hindenburg disaster. ^KILO-_LIMA 15:34, 27 January 2006 (UTC)[reply]

The evidence seems to suggest that a flammable coating on the outside of the Hindenburg is what caused the fire, although the hydrogen inside burnt, too. The bright orange flames described by witnesses are inconsistent with a straight hydrogen fire, which should be blue to clear. So, while hydrogen is flammable, so is gasoline. There is one thing that makes hydrogen worse, though, the need to store it either pressurized or at very low temps to make it liquid. A leak in a pressurized system is likely to leak a lot more than in an unpressurized system, so that's the problem there. The low temp storage will cause hydrogen to boil off as it warms up, so it will need to be vented continuously, which is also a fire hazard. Also, a massive leak of liquid hydrogen could be deadly even if it doesn't catch fire. If the occupants were doused in liquid hydrogen they could die or suffer severe "burns". StuRat 20:14, 27 January 2006 (UTC)[reply]

About your suggestion of nuclear energy. An advantage that has over solar and wind power is that it is a more reliable source (in case there is no sun or wind). But since this is about producing energy storage (in the form of hydrogen) that doesn't matter. Also, a problem with cars is that they are designed to carry their own power supply with them, which is rather inefficient - in order to transport one person you have to lug along a machine that weighs over ten times more than that person. So use wind or sun, store in hydrogen when there is excess energy to burn when there isn't enough (avoids transportation and pressurisation problems), and use the electricity to drive alternating magnets under the roads that magnets in cars can use to propell themselves. Of course this requires a serious change in the infrastructure - all infrastructure. Might there be a better way to propell cars with an external energy source? DirkvdM 14:01, 28 January 2006 (UTC)[reply]

The millions of square km that would need be covered with solar panels and/or windmills to supply all the energy currently supplied by gasoline would create quite a "visual blight" as well as environmental damage from plants that would no longer get sunlight, etc. The magnetic fields in the road might also pose a health hazard, especially in "sports cars" where the people ride low to the ground. Also note that a breakdown in the system would leave thousands stranded, which could be deadly in extreme weather (when such a failure is likely). I would suggest some onboard backup system be available that could get cars home, possibly at reduced speeds, when this happens. StuRat 15:06, 28 January 2006 (UTC)[reply]

I estimate from [14] that the world power consumption is about 14000 GW. Sun#The_Sun_as_a_power_source says we get about 1400 W/m² (that's all the power including the power cuaght in the atmosphere, which will be turned into wind, I suppose). So we'd need 10 million m². And Earth's surface is 510 million m². Harvesting 1/50 of the power is indeed quite a lot, considering the conversion inefficiencies. I'm amazed. Why is this simple fact never pointed out? (Except by you, that is, but then who listens to you? :) ) Or did I make a mistake in my estimate? DirkvdM 18:58, 28 January 2006 (UTC)[reply]

Oh dear me, yes, I made a mistake. I should of course not have taken the total surface of the Earth but the surface of the 'silhouette' (or what should I call that?). So it would be even worse, about 1/10.

I edited out the cross out because it was negativelly impacting the rest of the page all the way down. User:AlMac|^(talk) 22:39, 28 January 2006 (UTC)[reply]

Let me start over. [15] sugests we consume about 14000 GW, or 1.4x10¹⁰ W. Solar constant says we get 1.740×10¹⁷ W. So we receive 10 million times what we need. DirkvdM 19:24, 28 January 2006 (UTC)[reply]

This looks familiar. See orders of magnitude (power) for more measures of power consumption. ‣ᓛᖁ

ᑐ 19:42, 28 January 2006 (UTC)[reply]

Linux iwconfig

OK, I'm a newcomer to Linux, so try to ignore the stupidity of my questions and to try to give a simple answer. ;)

I'm trying to connect Knoppix on a LiveCD to my wireless router. I've used ndiswrapper to successfully install the Windows drivers for my Netgear WG511v2 PCMCIA wireless adapter card, and modprobed it so it shows up in iwconfig as wlan0. I can use it to scan for wireless networks and I do find my own wireless network in the list. It is WEP-encrypted, and I'm having trouble connecting it. At first, when I execute configuring commands like iwconfig wlan0 essid "SpeedStream9197", the settings in iwconfig are recorded. But as I start to put in more settings, I start losing the old ones, and eventually I find myself unable to set anything in iwconfig anymore. Any suggestions to what is going on, or have I missed something incredibly simple? -- Daverocks (talk) 11:25, 27 January 2006 (UTC)[reply]

Knoppix has a "networking" control panel which takes care of most of it for you, and it wouldn't surprise me if some of your problems are that you're "undermining" the control panel's work with your attempts at specifying things manually.

When you have multiple networks available to you, listing them and/or specifying which one you want to use under Linux is tricky. Using the essid subfunction of the iwconfig command, as you suggest, seems to help, but you have to do it at the right time. For example, I think I remember going through a routine where I'd type the iwconfig essid command in one window but not hit RETURN, then go to the Knoppix networking control panel and configure everything else and click "Enable", then quick go back to the terminal window and hit RETURN so the iwconfig command would take effect during the control panel's autonegotiation attempts, and then everything would work. Steve Summit (talk) 14:09, 27 January 2006 (UTC)[reply]

Would kwifimanager be this "control panel"? I tried running that, and it told me it couldn't start some service, and therefore it couldn't work properly? I'm going to have to check what it says again to give you a more detailed error message. But the GUI for it came up anyway, although it did not do anything because of the problem. -- Daverocks (talk) 19:47, 27 January 2006 (UTC)[reply]

I dunno. Maybe. I always got to it the WIMPy way, by clicking on "Networking" in a "System Configuration" menu somewhere. Steve Summit (talk) 20:34, 27 January 2006 (UTC)[reply]

I found a better way to configure it; wlcardconfig. You enter in everything and it does all the commands for you. Everything is set properly except the essid configuration. That's the only thing that doesn't save. I also found a GUI that has configuration options, probably similar or identical to the one you mention. Again, doesn't seem to have any effect on setting the essid. Do you remember exactly how you did that essid trick? I would be very happy to know. -- Daverocks (talk) 21:51, 27 January 2006 (UTC)[reply]

Solved the problem! I was setting the WEP key in restricted mode (its default) which might have something to do with stopping me from choosing a specific access point (?) Anwyay, I just put it on "Open" mode and it all works! GO LINUX! :) -- Daverocks (talk) 09:31, 28 January 2006 (UTC)[reply]

Converting .wma to .mp3

I borrowed some Music CD's from a friend and copied their contents on to my hard-disk.Coz I used Windows Media Player,the tracks are in the .wma format.I need to convert them to the mp3 format.How can I do that?Those CD's are not available now so I cant rip them directly.Some help required. Thnx in advance.

Well, you could decode them to an intermediate format such as uncompressed wav, then re-encode them to MP3, however, as both WMA and MP3 are lossy formats - that is, they degrade sound quality as part of their means of making the files smaller - your files will suffer quality loss from both the WMA encoding and then the MP3 encoding, and will most likely sound abysmal. As for which software to use, many open source and freeware audio players have the ability to convert audio formats to wav - off the top of my head, I believe Winamp can both play WMA and convert it to wav, and CDex can encode wav to MP3 --Noodhoog 13:14, 27 January 2006 (UTC)[reply]

Thnx for the reply but it doesn't help me because Winamp can only convert to .wav from CD's directly.Just like Music Match JukeBox,which can rip only CD's,not tracks from the hard-drive. Thus this isn't a solution. Thnx anyway.

[16] It's for an older version, but the instructions are similar for version 5. enochlau (talk) 17:10, 27 January 2006 (UTC)[reply]

Under the Microsoft EAUL license, which you accepted (because you use Windows Media Player) you cannot—repeat cannot—change a .wma file to a .mp3 file. You can convert a mp3 file to a wma file, but not the other way around. ^KILO-_LIMA 15:44, 27 January 2006 (UTC)[reply]
- That's funny, I can't seem to find the EULA for WMP 10. Do you know where I can get a hold of it? enochlau (talk) 17:20, 27 January 2006 (UTC)[reply]

The fundamental problem is that WMA format is not designed to let you do what you want to do here. Moreover, it is specifically designed not to let you do what you want to do here. Microsoft doesn't want you converting those WMA files into any other format at all (let alone the popular but unprotected mp3 format), because in this case, it is more interested in keeping the record companies happy than it is in keeping you happy.

Um, you know you can tell media player to save the files it copies as high quality mp3 files, negating the need to convert them--64.12.116.74 22:47, 27 January 2006 (UTC)[reply]

There are probably programs out there that can convert from WMA to mp3, but they are not going to be easy to find, because if they were easy to find, Microsoft would have found them and gotten them suppressed under the DMCA. There are probably people (here) who could tell you about those programs, but they're reluctant to, because telling people how to defeat copy protection can get you in almost as much trouble as defeating copy protection, which can get you in almost as much trouble (more trouble, really) than actually violating copyright.

Steve Summit (talk) 16:19, 27 January 2006 (UTC)[reply]

Why so hush hush? dBpowerAMP has always done the trick for me. Of course, if the content is protected by DRM, nothing's going to conver them, but if they're unprotected, this should do. enochlau (talk) 17:08, 27 January 2006 (UTC)[reply]

Well since you ripped them yourself using WMP, then there should be no protection actually (unless you chose to apply it yourself, and then you only have yourself to blame!) enochlau (talk) 17:10, 27 January 2006 (UTC)[reply]

I use GoldWave to open WMA files and save them as WAV. Then it's just convert to MP3. It's not very wise, but I don't really have WMAs of files I want in high quality, so to hell with quality when I do this. WMA sucks. ☢ Ҡieff⌇↯ 18:45, 27 January 2006 (UTC)[reply]

A quick and easy (though somewhat unrefined and inefficient) method is to get WMP to burn the files to disc, if that's possible, and then rip the CDs with another program that makes MP3s. Sum0 22:31, 27 January 2006 (UTC)[reply]

Um, you know you can tell media player to save the files it copies as high quality mp3 files, negating the need to convert them--64.12.116.74 22:47, 27 January 2006 (UTC)[reply]
- S/he's already converted them, and presumably doesn't have the original CD? But even if so, it's a good question. Don't put people off like that. enochlau (talk) 22:51, 27 January 2006 (UTC)[reply]
  - I didn't really think I was putting anyone off, it's just all the responses so far seem to imply that microsoft doesn't let you copy content in mp3, when that is actually a false statement--64.12.116.74 22:54, 27 January 2006 (UTC)[reply]
    - Oh right, fair enough. I guess it's something s/he can remember to do for next time ;) enochlau (talk) 22:55, 27 January 2006 (UTC)[reply]

carcinogens

What common foods contain carcinogens ? ie: tea , coffee, bacon etc

I believe when you burn foods you create carcinogens (I mean burn as in fire, not as is metabolize). StuRat 14:37, 27 January 2006 (UTC)[reply]

Well-done steak (which I like) is known to be much more likely to give one cancer than medium steak. With my luck, however, I'd be suprised to live long enough to get cancer. Captain Jackson 15:32, 27 January 2006 (UTC)[reply]

Answer here. (Also here, here, and here.) Steve Summit (talk) 16:36, 27 January 2006 (UTC)[reply]

I read somewhere that table salt caused stomach cancer, but that made no sense to me. Your body is full of sodium and chloride ions. —Keenan Pepper 18:00, 27 January 2006 (UTC)[reply]

I hadn't heard that. Iodine is also added to table salt to prevent goiters, but that isn't carcinogenic either, as far as I know. StuRat 20:05, 27 January 2006 (UTC)[reply]

Researchers in Japan [17] and Poland [18] have linked table salt to stomach cancer. According to the American Cancer Society:

There is some evidence that diets containing large amounts of food preserved by salting and pickling are related to increased risk of cancers of the stomach, nose, and throat. Little evidence suggests that moderate amounts of salt or salt-preserved foods in the diet affect cancer risk. [19]

‣ᓛᖁ

ᑐ 20:43, 27 January 2006 (UTC)[reply]

I smell a (horrendously large) List of suspected carcinogens article coming on... --P e ruvianLlama^(spit) 04:02, 28 January 2006 (UTC)[reply]

We already have those! See List of IARC Group 2A carcinogens and List of IARC Group 2B carcinogens. ^_^

‣ᓛᖁ

ᑐ 06:00, 28 January 2006 (UTC)[reply]

Many years ago, a magazine ran a competition for spurious scientific principles. My favourite was "if a rat is experimented upon, it will develop cancer". Notinasnaid 08:11, 28 January 2006 (UTC)[reply]

Counter-Strike and Weapons Copyrights

The computer-game Counter-Strike:Source contains a variety of computer models of real weapons. All of the weapons except the Mac-60 have fake names in the actual game because of copyright restrictions. However, if you go to the console screen it says that player X killed player Y using the real name of the weapon. Why do they have sneak around with the naming in the main game, but not the console? Plus they do alter a lot of the weapons' accuracy and damage abilities, making them less realistic, so why is it ok to use the weapon but not the name? Captain Jackson 15:30, 27 January 2006 (UTC)[reply]

Back when Counter-Strike was a free, user-made mod of Half-Life 1, it used the real names of weapons both on screen and in the console. Technically speaking, this was a breach of the trademarks on the names of the weapons, but a free mod was unlikely to catch the attention of the weapon manufacturers. After the mod was bought-out by Valve, the on-screen names changed to non-trademarked versions (since a real company with actual assets is more likely to be sued). Apparently, games such as Rainbow Six that use real weapon names actually have a licence agreement with, e.g., Heckler & Koch, to use the real names.

For some reason, Valve didn't bother changing the CS console messages, perhaps because that would have meant re-writing the code (the names are actually C++ functions in the source code, e.g. weapon_famas) and it would also have broken things like buy scripts that lots of people used. Perhaps Valve figured that changing the on-screen name was a sufficient change to avoid trademark trouble, even though the appearance and console names still matched.

The Source version of CS uses a similar weapon-naming scheme as the original CS. You can download a small file that tweaks the weapon names back to the original "real" names, should you want to. --Bob Mellish 16:15, 27 January 2006 (UTC)[reply]

How do I create public read-only variables (properties) in a PHP class?

I know how to create a public variable that's readable and writeable both inside and outside the class (public $varName;), however I want it to be read-only from outside the class while still readable and writeable from inside the class, without having to write a wrapper function for each variable. I’m not sure if PHP can even do this, so if anyone has any idea other than a wrapper class, please post them.

I think you just have to make the variable private and write an accessor method. Alternatively you could make it public, and specify in the documentation of your class that changing it may cause undefined behavior. —Keenan Pepper 17:55, 27 January 2006 (UTC)[reply]

Buying Electricity

Discussions about electric bills often come up where I work, and the issue of power factor relating to what you use and what you're billed for is often raised. Many suggest that the utility company charges for the uncorrected power you use, using peak current. This would mean that they are actually charging for KVA/H instead of KW/H, which would be deceptive at best. Does anyone know the metering method of typical house KW/H boxes that the util co's use to charge for power in the US? I didn't find much specific info in our Electricity Distribution category. --Jmeden2000 17:43, 27 January 2006 (UTC)[reply]

Isn't the kilovolt-ampere-hour exactly the same unit as the kilowatt-hour? I don't understand what you mean by "charging for KVA/H instead of KW/H". —Keenan Pepper 17:50, 27 January 2006 (UTC)[reply]

Incidentally, its quite different. This is why the issue is so often raised around my workplace, being a power systems company. See our article on Power factor for a detailed explanation. Essentially the issue is that in AC power supplies for modern things like TVs and computers, the draw from the line is non-sinusodial. Calculating the power based on peak amperage converted to RMS is inaccurate (resulting in a VA rating that is higher than W). Calculating power based on amperage at a higher resolution, ignoring the sine wave, results in a more accurate measure of consumption (meaning W reflects *actual* power usage over time). Power factor of devices is typically .7 (this is the defacto industry standard that my company uses), meaning that if you look at the metered VA draw it is 30% higher than the metered W. --Jmeden2000 18:34, 27 January 2006 (UTC)[reply]

Not to stop anyone from pondering this... but I found a fairly good answer after more reading in the Electric Power category's article on Electricity meter (should that article be attached to Category:Electricity_distribution?), which explains that most common meters use a method that does not account for reactive power and hence would meter true wattage. Although, it's not terribly specific so if anyone has more info I would love to hear it. --Jmeden2000 18:43, 27 January 2006 (UTC)[reply]

My understanding is that for a power company to charge for KVA/H isn't really quite so evil. (Nor would I call it particularly deceptive, since everyone knows about it -- everyone who knows about power factor, that is.) True, you didn't get any useful work out of those off-phase amps, and the power company didn't have to pay for fuel to generate them, but they did have to pay for copper in the transmission system to carry them. Those off-phase amps contribute to the current load (i.e. take their share of a cable's current capacity or "ampacity") just as much as the real, work-performing amps do.

Now, my understanding was also that, traditionally, small residential users are typically billed for KW/H (i.e. "fairly" from the work/energy perspective), and that the power company "eats" the power factor losses, or pays out of its own pocket for capacitor banks at substations to correct for them. However, large, high-current industrial users are typically billed for KVA/H, which gives them an incentive to install their own capacitors (if necessary) to keep their power factor near 100%. (But it wouldn't surprise me if, over time, more and more customers, even individual residential customers, are being billed for KVA/H. I just checked, and my electric meter is very clearly labeled "Watthour meter" and its display as indicating "kilowatthours", and so is the new, fancy-schmancy, electronic electric meter my neighbor has. If I had a big inductive load I'd perform an empirical test, but I don't.) Steve Summit (talk) 19:05, 27 January 2006 (UTC)[reply]

I'd like to point out that, as long as all power companies do it the same way, it doesn't matter, since they charge whatever either competition or the state governments will let them get away with. For example, if a utility sells one billion tweebles of power each year and it costs them a billion dollars, the state government may allow them to charge $1.10 per tweeble for a fair profit of 10%. On the other hand, if they claim they sell two billion tweebles a year at a cost of a billion dollars, the state would allow them to charge $0.55 per tweeble for a fair profit of 10%. So, the cost to the consumers will be $1.1 billion, either way you do it. In areas where different power companies compete, the forces of competition would dictate a similar outcome. StuRat 19:54, 27 January 2006 (UTC)[reply]

Well, it matters at least a little bit, because a KVA/H is not merely some constant fraction of a KWH. Consumers have some if not complete control over the power factor of their loads, and since low power factor loads are wasteful to the system, it's worthwhile to give people an economic incentive to raise their power factor. Steve Summit (talk) 23:55, 27 January 2006 (UTC)[reply]

How to put out a fire

How do water and carbon dioxide put out fires, especially when their individual atomic components (hydrogen-great fire fuel, oxygen-essential for fire, carbon-will burn, such as coal) would each support a fire by themselves? I am aware this has something to do with electrons and oxidation/reducation. Captain Jackson 18:00, 27 January 2006 (UTC)[reply]

Hmm, sounds a little like a homework question to me. =P Just keep in mind that a compound (NaCl is table salt) may share none of the properties of its component elements (Na bursts into flame on contact with water; Cl₂ is a poisonous gas). —Keenan Pepper 18:02, 27 January 2006 (UTC)[reply]

Exactly. If water tossed onto fire could burst into flame because of its hydrogen content, we would have to expect table salt to be terribly toxic due to its chlorine content. (Though wasn't someone just asking about NaCl as a suspected carcinogen? Also, thinking about water bursting into flame, I can't help but be reminded of Beaker's disastrous experience in Muppet Labs with "flammable water".)

In effect, the hydrogen in water is already "burned". You can pull the two components of water apart to create hydrogen and oxygen gas (in fact I think we were just talking about that here, too), but it takes exactly as much energy as you'd get back if you burned the hydrogen, so it doesn't tend to happen by itself.

With that said, though, I've heard that you can't put out an aluminum fire with water, and that aluminum will burn underwater, because it's so electronegative that it rips the oxygen out of the water itself, leaving hydrogen that will burn. (Come to think of it, the standard labratory demonstration of dropping lithium or sodium into water does the same thing.) Steve Summit (talk) 19:18, 27 January 2006 (UTC)[reply]

Never heard of this happening with Aluminum, Magnesium will do this, though.

This is just out of curiosity, I'm a senior in college who will never take another science class as long as I live. I've actually completed an organic chemistry course. Captain Jackson 18:14, 27 January 2006 (UTC)[reply]

Maybe a better question would be how matter can put out fire, a form of energy. Captain Jackson 18:15, 27 January 2006 (UTC)[reply]

Oh, my apologies. Fire fighting has some useful information about this. The goals are simply to separate the fuel from the oxygen, and absorb heat. Water does both. It boils into water vapor which pushes the oxygen away, and it absorbs heat because of its heat capacity. Also see fire triangle. —Keenan Pepper 18:28, 27 January 2006 (UTC)[reply]

Carbon dioxide is heavier than air, so sits on top of the fire, depriving it of free oxygen, and cools as it expands out of the extinguisher, then cools off the fire as well. Water evaporates as it hits the fire. If you've boiled water, you know how much energy it takes to boil it all off. And the main advantage of water is that it's so cheap you can pour huge quantities on the fire. Never use water on a grease fire or an electrical fire, though, as it will splatter flaming grease and conduct electricity. StuRat 19:42, 27 January 2006 (UTC)[reply]

It is true that CO2 is heavier than air, but that's not going to matter much with the fierce air currents that a fire makes. If you blow a stream of CO2 at a fire from an extinguisher, it's directed into a jet by the nozzle and it's its own momentum that keeps it moving toward the fire, just like when you play water on the fire from a hose. As stated above, its action is to cool the fire and deprive it of oxygen. --Anonymous, 09:50 UTC, January 28.

Mind and Brain

im doing a bit of coursework which includes a certain area of psychology and the mind, the question being, does the mind use the brain or does the brain use the mind? anyone who could answer would be great User:Alice cf83

From our article, the Mind: "The mind is the term most commonly used to describe the higher functions of the human brain"

To clarify this, the human brain is the physical organ contained within the skull with many functions, divided into "lower" and "higher" orders. The "lower" orders include involuntary activities, such as respiration, while the "higher" orders include mental activity, such as thought. As previously stated, the "mind" describes a collection of these "higher" functions. I would personally conclude therefore, that the mind uses the brain. For further reading, aside from our articles on the human brain and the mind, I would suggest this external link: Dualism: The Mind-Brain Problem. Hope this helps! --Lox (t,c) 22:15, 27 January 2006 (UTC)[reply]

We also have an article on the mind-body problem. ‣ᓛᖁ

ᑐ 06:11, 28 January 2006 (UTC)[reply]

I generally second Lox's answer. Suffice to say that you've asked an ancient and intractable problem of Western philosophy. There are people who are famous in no small part for their amusing ideas about this topic. --George 05:56, 28 January 2006 (UTC)[reply]

Well, philosophy probably is relevant to this question, but strictly speaking psychology doesn't... do the mind-body problem, does it? --Sum0 10:46, 28 January 2006 (UTC)[reply]

Does the book use the story it tells or does the story use the book it's in? Some claim there are no stupid questions. Such people obviously haven't studied philosophy. :) DirkvdM 14:10, 28 January 2006 (UTC)[reply]

computer files

I was wondering why it's important to back up files? Thank you, Funk Posse

See backup. Gdr 22:14, 27 January 2006 (UTC)[reply]

My computer crashed last week (I'm currently using a loan machine). My last backup was in August. So everything I've done on the computer since then may have been lost: My diary, my writing, my financial records, my music, my art... next question, please? Grutness...wha? 22:39, 27 January 2006 (UTC) (still in shock)[reply]

I'd be happy to tell you why it's important, but unfortuately I stored that answer on my ZIP disk, which is now unreadable. So I don't know anymore. - Nunh-huh 22:41, 27 January 2006 (UTC)[reply]

Lol, who still uses zip disks?--64.12.116.74 22:45, 27 January 2006 (UTC)[reply]

That's sort of the point. - Nunh-huh 08:03, 28 January 2006 (UTC)[reply]

What's a zip disk? Asking this makes me feel young for a change. :)

More seriously, especially make a point of regularly backing up texts you've written. I keep them together in a separate directory, which is very small because texts hardly take up any space. That way you can easily backup the whole lot regularly and have dozens of backups in the long run, without it really costing much. The chances of all backups of a file becoming unusable are then negligent. Unless you keep them all in the same room, which then burns down. So put them on some website as well. There are free ones for that, though I can't remember any right now. DirkvdM 14:16, 28 January 2006 (UTC)[reply]

It's important also to realise (and some people don't) that to be a backup there must be at least two copies. For instance, if you copy your photos to a CDROM from your hard drive, you have a backup. If you now remove them from the hard drive, you do not have a backup, even though the CDROM was originally a backup. On the other hand, if you made two CDROMs you do have a backup. This may not help if you keep them both together and the same disaster strikes. To plan backups you should consider all of the following possibilities: (a) computer failure loses files (hard disk wears out, nasty virus); (b) you, a friend or visting child deletes files, or destroys them (e.g. accidentally deleting a chapter of your novel without noticing, then saving); (c) computer is stolen; (d) computer is damaged by file, flood or other disaster. Remember that in cases (c) and (d) backups kept with or near the computer may be gone too (thieves tend to grab all sorts of stuff, and fire isn't picky). So called "backups" to files on the same disk are quick and easy, but only protect against case (b). Notinasnaid 17:34, 28 January 2006 (UTC)[reply]

BitTorrent

Do torrents work at all from behind a router?--64.12.116.74 22:56, 27 January 2006 (UTC)[reply]

I have a router and mine work fine. Perhaps you are thinking of a firewall. --Kainaw ^(talk) 23:14, 27 January 2006 (UTC)[reply]

If you are behind a home broadband router which is doing NAT, you may need to do some setup to direct incoming BitTorrent connections to the correct computer. How you'd do this depends on your router; for details of what ports you should open, Google is your friend. -- AJR | Talk 01:47, 28 January 2006 (UTC)[reply]

In fact, BitTorrent works fine behind a NAT without any setup; you'll just not be able to connect to other peers which are also behind a NAT or a firewall (this sometimes can be a problem on less popular torrents, and you will get slower downloads). --cesarb 02:52, 28 January 2006 (UTC)[reply]

Depending on your specific situation, Port forwarding and Port triggering might also have relevant info. For a non-Wiki source, check out the BitTorrent.com FAQ. --P e ruvianLlama^(spit) 03:48, 28 January 2006 (UTC)[reply]

January 28

Early film technology questions

Hey, I'm working on a big table comparing film formats by specs and I'm still looking for a few pieces of information with little luck. Here are some:

What are the projector aperture dimensions for Pathe Kok format?
What is the pulldown for Cineorama (not Cinerama)?
What are the gate aperture and projector aperture dimensions for Movietone?
What is the first Movietone film with optical sound down the side?
What is the first film shot in Academy ratio?
What was the first film matted down to 1.75?
What was the first film matted down to 1.85?

I may have more in the future, but that's plenty for now. Any answers with references most greatly appreciated! Thanks in advance. Girolamo Savonarola 01:41, 28 January 2006 (UTC)[reply]

Welcome to Wikipedia, the free encyclopedia. Perhaps you didn't realize this, but this is actually an on-line encyclopedia where you can answer most questions yourself using the handy search bar along the left side of your screen. Type in "film", press "Go", and marvel at the wonder that is modern technology. In your case, you will need to use the box with the "Go" button several times, for several key words, and also explore links you find on those articles to related articles.

Many articles are grouped into categories (see links at bottom of pages) You might like to explore some of the articles in categories such as the following.

User:AlMac|^(talk) 08:23, 28 January 2006 (UTC)[reply]

Re:5. According to this link Thomas Edison already shot his films in 1.37:1, but of course at the time it wasn't called Academy ratio. It was made into a standard by the Academy of Motion Picture Arts and Sciences in 1932. David Sneek 09:26, 28 January 2006 (UTC)[reply]

Just wanted to point out that User:Girolamo Savonarola is a major editor of Wikipedia's film technology articles. --Shantavira 18:13, 28 January 2006 (UTC)[reply]

how do I become a reference desk volunteer?

I'm good with science in particular, but know a bit about a lot. I'd love to help answering people's questions.

Thank you, Jon Boro

Just like everything else on Wikipedia, just go in and do it! I love doing this now that I've found it! --

Mac Davis ☢ ญƛ. 09:10, 28 January 2006 (UTC)[reply]

Note the "edit" button on the right of each heading. To answer that question, simply click "edit" and go nuts. - Akamad 09:33, 28 January 2006 (UTC)[reply]

Also, be sure to put a colon before each response, and if it is a reply to a response, then put two colons. And link words you may want to with the great four brackets. [[]] --

Mac Davis ☢ ญƛ. 09:58, 28 January 2006 (UTC)[reply]

Get an account too if you haven't already, and you can sign your contributions with ~~~~. For more info on contributing generally, see Wikipedia:Introduction. Enjoy! enochlau (talk)

Dermathology,Biology and Chemistry question

Hi, I was wondering if the slime of a snail has good properties for the skin, because I don't know if buying a cream that 'everyone' here is buying because it's supposed to be so good, so I have my doubts, is it actually regenerative and all? or all they say is just part of the publicity.--Cosmic girl 14:48, 28 January 2006 (UTC)[reply]

I, from personal experience, don't think it would be a good idea. What exactly do you want the slime to do to his/her/your skin? Age-reduction et al? A biologist and a dermatologist would have a much better answer than this. I suppose it doesn't really come under Chemistry. ^KILO-_LIMA 16:16, 28 January 2006 (UTC)[reply]

If it is made from the slime of multiple snails, it might signal "lots of food this way." If made from the slime of one snail, it might prolaim to other snails that this one owns you. alteripse 16:44, 28 January 2006 (UTC)[reply]

LOL! very funny alteripse, well I don't think it's supposed to be for anything in particular, it's just said to be a good moisturizer since it's natural and it's supposed to improve the overall skin condition,no matter what you have or don't have...and well I saw an advertisement on tv and it's such a persistent advertisement that everyone where I live is aware of this product and so once I made fun of it with one of my nicknames on MSN and a guy friend of mine told me that his mom had bought him the cream and that it's actually good because he had a scar and it began to dissapear, but whatever, I'm such a skeptic that I want to know if that thing has chemical properties that could actually be beneficial for the skin or if it's just a fraud like a lot of stuff that's sold on tv.--Cosmic girl 16:55, 28 January 2006 (UTC)[reply]

What's the name of this product? I suggest you Google it and see whether there has been any tests or critical research. Lots of things are "natural", but that doesn't necessarily mean they're good for your skin, or anything else. --Shantavira 18:19, 28 January 2006 (UTC)[reply]

Is this it? As so often happens, the write-up contains vague phrases like "laboratory studies have shown" without actually citing the studies. Your doctor should know whether this stuff is any good. Alternatively it looks as though you could just go find some snails to crawl on you. --Shantavira 18:39, 28 January 2006 (UTC)[reply]

hahaha! yeah I'd rather have snails crawl on me than use some dubious cream on my skin...I'll stay with my skepticism and not expose my skin to any risk.--Cosmic girl 19:40, 28 January 2006 (UTC)[reply]

Are snails noted for having particularly lovely skin? I think not. Conversely, would one describe a flawless complexion as "peaches and slime"? And cow poo is "natural", but I won't knowingly be applying any to my epidermis... - Nunh-huh 20:37, 28 January 2006 (UTC)[reply]

hahaha! :D ( if I ever know of anyone who got results I'll tell you though ;) ) --Cosmic girl 23:27, 28 January 2006 (UTC)[reply]

Cotton swabs and ear damage

While the cotton swabs article doesn't mention it, the Q-tips article indicates that swabs should not be used to clean ear wax from a person's ear canal. Why is this? What is the possible damage that could result? -User:Lommer | ^talk 18:42, 28 January 2006 (UTC)[reply]

Our article on earwax has an extensive section on the subject. It says:

It is generally advised not to use cotton swabs (Q-Tips or cotton buds) as these will likely push the wax further down the ear canal and, if used carelessly, perforate the eardrum or worse. Cotton swabs should be used only to clean the external ear.

That should answer your question. See the article for more info on cleaning the ear canal. ☢ Ҡieff⌇↯ 18:48, 28 January 2006 (UTC)[reply]

Of course, others say that these warnings are just a case of a manufacturer producing a product obviously designed for a specific purpose -- i.e. cleaning inside the ear canal -- and then attempting to avoiding lawsuit by claiming that it is intended for another purpose. Draw your own conclusions. --Anonymous, 20:40 UTC, January 28.

Battery Discharge

I need all the information I can get about battery discharge. I am participating in my local science fair and I need info to write the essay. I have been searching on the internet but all of the info is not quite right. I need to know about battery discharge in AA Alkaline batteries. Just the common household ones like Duracell and Energizer. I really Appreciate it, Thanks!

I once looked all this up to compare rechargeables, and see if Alkaline recharging really worked. There's a lot of information from the battery companies. If you are going to be successful in a science fair, you're going to have to become a pro at Google. --Zeizmic 20:39, 28 January 2006 (UTC)[reply]

Thanks, but I have already searched exstensively there, and have not found the info I was looking for. I need to answer a few questions: What is battery discharge? WHat does storing a battery in a cold temperature do? What does storing a battery at room temperature do? and What is the best way to store a battery? If you could answer these questions that would be great. Thanks! P.S.: I am looking for answers about non-rechargable batteries

Those are decent questions. They all boil down to one question though: What causes batteries to self-discharge? We should really have an article on self-discharging. -- Ec5618 21:24, 28 January 2006 (UTC)[reply]

Thanks, but my questions still haven't been answered. I would appreciate an answer, Thanks! Helen

Again, Google Aptitude is important. You should be able to find this [[20]] in 2 minutes. It answers all your questions. --Zeizmic 22:29, 28 January 2006 (UTC)[reply]

Thanks for the link, but it did not answer my questions. I am not looking for the numbers, but rather the basic information so I can do the experiment myself. Helen

BC pot laced with meth

I've tried going to UBC's web site to locate Dr. Bill MacEwen's statement that BC pot is laced with meth to get people addicted to pot. Nothing seems available. Can you suggest a starting point? Thanks, 198.166.18.60 21:59, 28 January 2006 (UTC)[reply]

I doubt that the Union Bank of California is likely to know much about methyl alcohol in cookware from Ensenada. How about giving a little more context? --Trovatore 22:07, 28 January 2006 (UTC)[reply]

University of British Columbia Canada. Crystal methamphetimine laced marijuana to make people more addicted to cannabis. First read about Dr. B. MacEwen at UBC in local newspaper. 198.166.18.60 22:48, 28 January 2006 (UTC)[reply]

Doesn't make a lot of sense -- it perhaps might get people addicted to meth, but who in the hell wants speedy pot? --jpgordon ∇∆∇∆ 22:59, 28 January 2006 (UTC)[reply]

Eyesight Damage From Optical Mice Light?

Is it possible? —The preceding unsigned comment was added by 12.27.185.151 (talk • contribs) .

I'm not sure why you'd think it might. It may be red, but it's a light-emitting diode, not a laser. - Nunh-huh 23:00, 28 January 2006 (UTC)[reply]

Some optical mice do use laser LEDs. I'd expect them to be class I, however (see laser safety). --cesarb 23:20, 28 January 2006 (UTC)[reply]

My own Logitech MX1000 Laser mouse is indeed a class I device. --GraemeL ^(talk) 23:35, 28 January 2006 (UTC)[reply]

How can I free up RAM?

What are some ways that I can free up some of my computer's RAM? I'm running a Dell Dimension 4100 with a Pentium III, 128 MB of RAM, and Windows ME. I'm trying to improve performance, because as it stands, I only have a tiny fraction of my RAM available... Javguerre

As I understand it, Windows views unused physical memory as a wasted resource, and will deliberately grab it, to reduce disk swapping. If you try to keep Windows from doing this, you'll probably worsen overall performance rather than improve it. If you're interested in the performance of one specific program, that's different: Then you could try rewriting it to manage its own memory allocation, and there's even an API call to lock pages in memory so they won't be swapped to disk. --Trovatore 23:39, 28 January 2006 (UTC)[reply]

No, I'm interested in doing whatever I can to better overall performance. I know defragmenting will help, but I'm curious as to whether or not there's anything else that can be done.

Lyapunov stability for state space models

The article says:

A state space model

${\dot {\textbf {x}}}=A{\textbf {x}}$ is asymptotically stable if

A^{T}M+MA+N=0

has a solution where $N=N^{T}>0$ and $M=M^{T}>0$ (positive definite matrices).

Does anyone have a proof for this? deeptrivia (talk) 23:37, 28 January 2006 (UTC)[reply]

@@ Line 2,465: / Line 2,465: @@
 What are some ways that I can free up some of my computer's RAM? I'm running a Dell Dimension 4100 with a Pentium III, 128 MB of RAM, and Windows ME. I'm trying to improve performance, because as it stands, I only have a tiny fraction of my RAM available... [[User:Javguerre|Javguerre]]
 :As I understand it, Windows views unused physical memory as a wasted resource, and will deliberately grab it, to reduce disk swapping. If you try to keep Windows from doing this, you'll probably worsen overall performance rather than improve it. If you're interested in the performance of one specific ''program'', that's different: Then you could try rewriting it to manage its own memory allocation, and there's even an API call to lock pages in memory so they won't be swapped to disk. --[[User:Trovatore|Trovatore]] 23:39, 28 January 2006 (UTC)
+::No, I'm interested in doing whatever I can to better overall performance. I know defragmenting will help, but I'm curious as to whether or not there's anything else that can be done.
 ==[[Lyapunov stability]] for state space models ==