Stephen Hawking

Stephen Hawking. Reuters/Stephen Hird

Stephen William Hawking, CH CBE FRS (born January 8 1942) is one of the world's leading theoretical physicists. Hawking is Lucasian professor of mathematics at the University of Cambridge (a post once held by Isaac Newton).

Biography

Hawking was born in Oxford, England to Frank and Isobel Hawking as their first child. He was educated at St Albans School, Hertfordshire and University College, Oxford, where he obtained a first class honours degree in physics. He moved to Cambridge University to complete his PhD in cosmology at Trinity Hall.

He was elected a Fellow of the Royal Society in 1974, appointed CBE in 1982 and became a Companion of Honour in 1989.

His principal fields of research are theoretical cosmology and quantum gravity. His major contributions to the field of research include his papers on the relationship between black holes and thermodynamics. His research indicated that black holes do not exist forever, but rather that virtual particle pairs created near their event horizons cause them to "evaporate" over time in a process known as Hawking radiation (although, in July 2004, he indicated that his theory that black holes destroy information was incorrect—see below). He is also known for his chronology protection conjecture which hypothesizes the theoretical impossibility of closed timelike curves.

In spite of being severely disabled by Motor Neurone Disease, he is highly active in physics, writing, and public life. He first began to show symptoms of the disorder while enrolled in Cambridge. He was diagnosed at the age of 21, shortly before his first marriage. At the time, doctors said he would not live more than about two or three years longer. He battled the odds and has survived much longer, although he has become increasingly disabled by the gradual progress of the disease. He has used an electronic voice synthesizer to communicate since he had a tracheostomy in 1985 following a severe bout of bronchitis. He gradually lost the use of his arms and legs and now almost cannot move. The computer system attached to his wheelchair is operated by Hawking manually through a device called "Clicker", which lets him select words and other options on his computer's screen, but can be controlled by head or eye movement as well.

Being remembered chiefly for his science, there is every chance that he would never have made the discoveries he has were it not for the support of his family. Although he divorced Jane in 1990 (they had 3 children - named Tim, Lucy and Robert - and now have a grandchild), Hawking is still something of a family man. Relationships drive him, not physics. In spite of his disease he describes himself as "lucky" - not just because its slow progress allowed him time to make influential discoveries but because it afforded him time to have, in his own words, "a very attractive family"[1]. When Jane was asked why she decided to marry a man with a 3-year life expectancy, she responded: "These were the days of atomic gloom and doom, so we all had rather a short life expectancy". He married his second wife Elaine Mason in 1995.

His two books A Brief History of Time and The Universe in a Nutshell have remained highly popular all over the world and are now classic best-sellers. Anyone interested in the universe, cosmos and how it all began can read them: no previous knowledge in this field is required to enjoy these books. A collection of essays by him - Black Holes and Baby Universes and Other Essays is also extremely popular.

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Hawking as himself on Star Trek TNG

In popular culture, he has become a widely admired figure as a genius who has had a successful life despite his severe disability. He had a guest appearance in an episode on the holodeck of the television series Star Trek: The Next Generation, playing poker with Data, Albert Einstein, and Isaac Newton in the episode "Descent, Part I." The animated television series The Simpsons and Futurama have occasionally featured him in episodes, and a character playing Hawking has appeared in the television series Dilbert. On Late Night with Conan O'Brien he participated in a bit with Jim Carrey. He also lent his voice to the Pink Floyd song "Keep Talking" from The Division Bell. A parody website even has a Hawking-like voice synthesizer rapping about physics [2]

Hawking is famous for his oft-made statement, "When I hear of Schrödinger's cat, I reach for my gun." This was a deliberately ironic paraphrase of Hermann Göring's anti-intellectual quote, "When I hear the word 'culture', I reach for my Browning", which itself was from a play by German playwright and Nazi Poet Laureate, Hanns Johst.

As well as his serious academic side, and humor, Hawking is an active supporter of different causes, having appeared on a party political broadcast for the Labour Party, and in actively supporting the children's charity, SOS Children's Villages. Reportedly he has also agreed to take part in a protest against the war in Iraq. [3]

Losing an old bet

Hawking was in the news in July 2004 for presenting a new theory about black holes which goes against his own long-held belief about their behaviour, thus losing a bet he and Kip Thorne made with John Preskill, a particle physicist. Classically, it can be shown that information crossing the event horizon of a black hole is lost to our universe. This is known as the no hair theorem. The problem with the no hair theorem is that it implies the black hole will emit the same radiation regardless of what goes into the black hole. So if you throw a pure quantum state into a black hole, you will get out a mixed state. This runs counter to the rules of quantum mechanics and is known as the black hole information paradox.

Hawking had earlier speculated that the singularity at the center of a black hole could form a bridge to a "baby universe" into which the lost information could pass; such theories have been very popular in science fiction. But according to Hawking's new idea, presented at the 17th International Conference on General Relativity and Gravitation, on 21 July, 2004 in Dublin, Ireland, black holes eventually transmit, in a garbled form, information about all matter they swallow.

The Euclidean path integral over all topologically trivial metrics can be done by time slicing and so is unitary when analytically continued to the Lorentzian. On the other hand, the path integral over all topologically non-trivial metrics is asymptotically independent of the initial state. Thus the total path integral is unitary and information is not lost in the formation and evaporation of black holes. The way the information gets out seems to be that a true event horizon never forms, just an apparent horizon.

--GR Conference website summary of Hawking's talk.

Having concluded that information is conserved, Hawking conceded his bet in Preskill's favor, awarding him Total Baseball, The Ultimate Baseball Encyclopedia, an encyclopædia from which information is easily retrieved. However, Thorne remains unconvinced of Hawking's proof and declined to contribute to the award.

Awards

Publications

Technical

The Large Scale Structure of Spacetime with George Ellis
...and many more

Satire

MC Hawking -- the imaginary alter-ego for the "theoretical physicist turned gangster-rapper"
The Simpsons -- made a guest appearance on the long running prime-time cartoon. His chair had unusual super-characteristics, including an Inspector Gadget style retractable helicopter attachment and a spring-loaded boxing glove.
Futurama -- made a guest appearance as part of a team guarding the space-time continuum, which included Al Gore, Nichelle Nichols (from Star Trek), and Gary Gygax
The Onion -- satirical newspaper ran an article claiming that Hawking's head had been mounted on a super-robotic cyborg body, complete with laser guided missiles and a jetpack. Hawking, with his typical good humor, sent them a letter cursing them for exposing his evil plans for world domination.

External links