Talk:Half-life and Minor white: Difference between pages

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+#REDIRECT [[Minor White]]
-To say that the constant 'a' is negative in the case of exponential decay leads to a very confusing developement (imho): the standard is to use the decay constant <math>\lambda</math>, which is positive: <math>\lambda = \frac{ln(2)}{t_{1/2}}</math>. One should write the exponential law as <math>x(t) = x(0) e^{-a t}</math>, and so there is no need to talk about the constant being able to absorb the minus sign, which is actually incorrect! (if <math>a</math> absorbs the minus sign, it becomes positive, that's indeed what we see in the last formula: <math>t_{1/2} = \frac{ln(2)}{a}</math> since ln(2) and <math>a</math> are positive. And since <math>a</math> is positive, there should be a minus signe in the exponent of the decay law). To make things even easier to understand, one may use N instead of x, it's probably a more natural way to represent the population of radioactive isotope which is an integer. (I leave it to other people to make the changes: my English is not very good).
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-I agreed with the above point, but the whole article needs some work IMO. I have flagged it as needing attention. The discussion on the half-life usage in physics seems to talk about lots of points that don't belong here. Perhaps these bits should be integrated into the [[radioactive decay]] article?
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-The structure doesn't seem that great either - there are lots of major headings containing only a sentence or two of description.
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-I don't understand the section on its usage in population calculation. Could someone clarify this or else remove this section.
-<p>There are probably other problems that I have forgotten... [[User:Bobbis|Bobbis]] 18:52, 26 Oct 2004 (UTC)
-== Of "particles", "substances", "radioactivity" and the like ==
-People like to use these words in this article, but strictly speaking, none of them have anything to do with half-life.  Half-life is a purely mathematical (theoretical) property of the likewise mathematical phenomenon of [[exponential decay]].  The differential equation that describes exponential decay crops up in a bunch of places; see [[Exponential decay]] for a list (which I'm sure is less than complete). --[[User:Smack|Smack]] 05:02, 10 Nov 2004 (UTC)
-==A little more simplicity might be in order==
-Imagine a high-school student -- or anyone who did not take more than first year college math.  Do you think they would get anything from this page or the one on exponential decay?
-I think the table is needed on BOTH pages, but even more so on the half-life page -- as it is more likely anyone who was not mathematically advanced would go there first.
-Anyone who was able to understand what has appeared on these pages would NOT need to look up the terms.
-No?
---[[User:JimWae|JimWae]] 04:35, 2004 Dec 20 (UTC)
-:I see two viable options: a) leave this article as it is, or b) put a thorough discussion of exponential and radioactive decay here.  (I disregard any intermediate compromise solution, as it would frustrate both your goals and mine to an equally great extent.)
-:I rewrote this article with Option A in mind, by purposely stripping it of everything not related to this narrow subject.  My hope is that the references to [[Exponential decay]] and [[Radioactive decay]] are prominent enough that people who see this article and wonder where all of the information is will go there.  Option B would involve simple duplication of material presented elsewhere, which encourages divergent evolution. --[[User:Smack|Smack]] 18:07, 20 Dec 2004 (UTC)
-:P.S: If you want to make this subject more clear to those with weak mathematical skills (or even short attention spans for math), I see no reason why you shouldn't.  I just have concerns about the way it's done. --[[User:Smack|Smack]] 18:12, 20 Dec 2004 (UTC)
-* I still think the simple table would make this a much more '''useful''' article for the overwhelming majority of readers. Those who understand the math here, would never need to look up the meaning.--[[User:JimWae|JimWae]] 20:55, 2004 Dec 31 (UTC)
-::What meaning?
-::I agree that this article is not very helpful.  I don't intend it to be helpful for most people.  It does not stand alone, except for narrow purposes.  People who come here with general questions are better off at [[Exponential decay]], and I think we should do our best to make sure they go there. The more general content we put here, the less likely that is to happen.  --[[User:Smack|Smack]] 18:45, 3 Jan 2005 (UTC)
-:Encyclopedia articles should be accessible to those who might open the page, not just be technically correct. Most people will more likely go to [[half-life]] first than [[exponential decay]]. Even if they manage to click on [[exponential decay]] after going to half-life (but why that link rather than any other there?), they are first going to see stuff way too technical for them there too. There is no real danger of significantly different versions with that table. If somebody understands either page, they already know what half-life means--[[User:JimWae|JimWae]] 07:03, 2005 Feb 18 (UTC)
-::You're right, [[exponential decay]] is not referenced prominently enough for inexperienced readers.  I'll tweak the intro paragraph a bit.
-::You're also right that that article is not very accessible to the non-mathematical.  IMO, the way to resolve that problem is not to slap half-hearted stand-in explanations of exponential decay onto other articles, but to write a qualitative treatment of the topic into the main article's introduction. If you consider yourself capable of doing that, please do so.  I wouldn't trust myself with the task. --[[User:Smack|Smack]] ([[User talk:Smack|talk]]) 03:45, 20 Feb 2005 (UTC)