Stephen William Hawking CH, CBE, FRS, FRSA (born 8 January 1942) is a British theoretical physicist. Hawking is the Lucasian Professor of Mathematics at the University of Cambridge (but intends to retire from this post in 2009),[1] a Fellow of Gonville and Caius College, Cambridge and the distinguished research chair at Waterloo's Perimeter Institute for Theoretical Physics.[2] He is known for his contributions to the fields of cosmology and quantum gravity, especially in the context of black holes, and his popular works in which he discusses his own theories and cosmology in general. These include the runaway popular science bestseller A Brief History of Time, which stayed on the British Sunday Times bestseller list for a record-breaking 237 weeks.
His key scientific works to date have included providing, with Roger Penrose, theorems regarding singularities in the framework of general relativity, and the theoretical prediction that black holes should emit radiation, which is today known as Hawking radiation, or sometimes as Bekenstein-Hawking radiation.[4] His scientific career spans over 40 years and his books and public appearances have made him an academic celebrity and world-renowned theoretical physicist. He is an Honorary Fellow of the Royal Society of Arts,[5] and a lifetime member of the Pontifical Academy of Science.[6] Hawking has amyotrophic lateral sclerosis (ALS). The condition has progressed over the years and he is now almost completely paralysed.
Stephen Hawking was born to Dr. Frank Hawking, a research biologist, and Isobel Hawking, a political activist. He had two younger sisters, Philippa and Mary and an adopted brother, Edward.[7] Though Hawking’s parents were living in North London, they moved to Oxford while Isobel was pregnant with Stephen, desiring a safer location for the birth of their first child (London was under attack at the time by the Luftwaffe).[8] According to one of Hawking's publications, a German Wehrmacht V-2 missile struck only a few streets away.[9]
After Hawking was born, the family moved back to London, where his father headed the division of parasitology at the National Institute for Medical Research.[7]
In 1950, Hawking and his family moved to St Albans in Hertfordshire where he attended St Albans High School for Girls from 1950 to 1953. (At that time, boys could attend the Girls school until the age of 10.[10]) From the age of 11, he attended St Albans School, where he was a good, but not an exceptional, student.[7] When asked later to name a teacher who had inspired him, Hawking named his Mathematics teacher, "Mr Tahta".[11] He maintains his connection with the school, giving his name to one of the four houses and to an extracurricular science lecture series. He has visited to deliver one of the lectures and has also granted a lengthy interview to pupils working on the school magazine, The Albanian.
Hawking was always interested in science.[7] He enrolled at University College, Oxford with the intent of studying mathematics although his father preferred he go into medicine. Since mathematics was not offered at University College, Hawking instead chose physics. His interests during this time were in thermodynamics, relativity, and quantum mechanics. His physics tutor, Robert Berman, later said in the New York Times Magazine:
It was only necessary for him to know that something could be done, and he could do it without looking to see how other people did it. ... He didn’t have very many books, and he didn’t take notes. Of course, his mind was completely different from all of his contemporaries.[7]
Hawking was passing with his fellow students, but his unimpressive study habits gave him a final examination score on the borderline between first and second class honours, making an "oral examination" necessary. Berman said of the oral examination:
And of course the examiners then were intelligent enough to realize they were talking to someone far more clever than most of themselves.[7]
After receiving his B.A. degree at Oxford University in 1962, he stayed to study astronomy. He decided to leave when he found that studying sunspots, which was all the observatory was equipped for, did not appeal to him and that he was more interested in theory than in observation.[7] He left Oxford for Trinity Hall, Cambridge, where he engaged in the study of theoretical astronomy and cosmology.
Almost as soon as he arrived at Cambridge, he started developing symptoms of amyotrophic lateral sclerosis (known colloquially in the USA as Lou Gehrig’s disease), a type of motor neuron disease which would cost him almost all neuromuscular control. During his first two years at Cambridge, he did not distinguish himself, but, after the disease had stabilized and with the help of his doctoral tutor, Dennis William Sciama, he returned to working on his Ph.D.[7] He revealed that he did not see much point in obtaining a doctorate if he were to die soon. Hawking later said that the real turning point was his 1965 marriage to Jane Wilde, a language student.[7] After gaining his Ph.D., Stephen became first a Research Fellow, and later on a Professorial Fellow at Gonville and Caius College.
Hawking was elected as one of the youngest Fellows of the Royal Society in 1974, was created a Commander of the Order of the British Empire in 1982, and became a Companion of Honour in 1989. Hawking is a member of the Board of Sponsors of The Bulletin of the Atomic Scientists.
Jane Hawking (née Wilde), Hawking’s first wife, cared for him until 1991 when the couple separated, reportedly due to the pressures of fame and his increasing disability. They had three children: Robert (b. 1967), Lucy (b. 1969), and Timothy (b. 1979). Hawking married his nurse, Elaine Mason (who was also the previous wife of David Mason, designer of the first version of Hawking’s talking computer), in 1995. In October 2006, Hawking filed for divorce from his second wife.[12]
In 1999, Jane Hawking published a memoir, Music to Move the Stars, detailing her own long-term relationship with a family friend whom she later married. Hawking’s daughter, Lucy, is a novelist. Their oldest son, Robert, emigrated to the United States, married, and has one child, George Edward Hawking. Reportedly, Hawking and his first family were reconciled in 2007.[13]
At the celebration of his 65th birthday on 8 January 2007, Hawking announced his plans for a zero-gravity flight in 2007 to prepare for a sub-orbital spaceflight in 2009 on Virgin Galactic’s space service. Billionaire Richard Branson pledged to pay all expenses for the latter, costing an estimated £100,000.[14] Stephen Hawking’s zero-gravity flight in a "Vomit Comet" of Zero Gravity Corporation, during which he experienced weightlessness eight times, took place on 26 April 2007.[15]
He became the first quadriplegic to float in zero-gravity. This was the first time in 40 years that he moved freely, without his wheelchair. The fee is normally US$3,750 for 10-15 plunges, but Hawking was not required to pay the fee. A bit of a futurist,[16] Hawking was quoted before the flight saying:
Many people have asked me why I am taking this flight. I am doing it for many reasons. First of all, I believe that life on Earth is at an ever increasing risk of being wiped out by a disaster such as sudden nuclear war, a genetically engineered virus, or other dangers. I think the human race has no future if it doesn’t go into space. I therefore want to encourage public interest in space.[17]
[edit] Research fields
Hawking’s principal fields of research are theoretical cosmology and quantum gravity.
In the late 1960s, he and his Cambridge friend and colleague, Roger Penrose, applied a new, complex mathematical model they had created from Albert Einstein’s general theory of relativity.[18] This led, in 1970, to Hawking proving the first of many singularity theorems; such theorems provide a set of sufficient conditions for the existence of a singularity in space-time. This work showed that, far from being mathematical curiosities which appear only in special cases, singularities are a fairly generic feature of general relativity.[19]
He supplied a mathematical proof, along with Brandon Carter, Werner Israel and D. Robinson, of John Wheeler’s “No-Hair Theorem” – namely, that any black hole is fully described by the three properties of mass, angular momentum, and electric charge.
Hawking also suggested that, upon analysis of gamma ray emissions, after the Big Bang, primordial or mini black holes were formed. With Bardeen and Carter, he proposed the four laws of black hole mechanics, drawing an analogy with thermodynamics. In 1974, he calculated that black holes should thermally create and emit subatomic particles, known today as Hawking radiation, until they exhaust their energy and evaporate.[20]
In collaboration with Jim Hartle, Hawking developed a model in which the Universe had no boundary in space-time, replacing the initial singularity of the classical Big Bang models with a region akin to the North pole: One cannot travel North of the North pole, as there is no boundary there. While originally the no-boundary proposal predicted a closed Universe, discussions with Neil Turok led to the realisation that the no-boundary proposal is also consistent with a Universe which is not closed.
Among Hawking’s many other scientific investigations, included are the study of: quantum cosmology, cosmic inflation, helium production in anisotropic Big Bang universes, large N cosmology, the density matrix of the universe, topology and structure of the universe, baby universes, Yang-Mills instantons and the S matrix, anti de Sitter space, quantum entanglement and entropy, the nature of space and time, including the arrow of time, spacetime foam, string theory, supergravity, Euclidean quantum gravity, the gravitational Hamiltonian, Brans-Dicke and Hoyle-Narlikar theories of gravitation, gravitational radiation, and wormholes.
At a George Washington University lecture in honour of NASA's 50th anniversary, Prof. Hawking theorised on the existence of extraterrestrial life: "Primitive life is very common and intelligent life is fairly rare."[21]
Main article: Thorne-Hawking-Preskill 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 behavior, thus losing a bet he made with Kip Thorne and John Preskill of Caltech. Classically, it can be shown that information crossing the event horizon of a black hole is lost to our universe, and that thus all black holes are identical beyond their mass, electrical charge and angular velocity (the “no hair theorem”). The problem with this theorem is that it implies the black hole will emit the same radiation regardless of what goes into it, and as a consequence that if a pure quantum state is thrown into a black hole, an “ordinary” mixed state will be returned. 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 centre 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, Republic of 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.[22]
”
Having concluded that information is conserved, Hawking conceded his bet in Preskill’s favour, awarding him Total Baseball, The Ultimate Baseball Encyclopedia. Thorne, however, remained unconvinced of Hawking’s proof and declined to contribute to the award.[23] Another older bet – about the existence of black holes – was described by Hawking as an “insurance policy” of sorts. To quote from his book, A Brief History of Time:
“
This was a form of insurance policy for me. I have done a lot of work on black holes, and it would all be wasted if it turned out that black holes do not exist. But in that case, I would have the consolation of winning my bet, which would win me four years of the magazine Private Eye. If black holes do exist, Kip will get one year of Penthouse. When we made the bet in 1975, we were 80% certain that Cygnus was a black hole. By now, I would say that we are about 95% certain, but the bet has yet to be settled.
”
1975 Eddington Medal
1976 Hughes Medal of the Royal Society
1979 Albert Einstein Medal
1982 Order of the British Empire (Commander)
1985 Gold Medal of the Royal Astronomical Society
1986 Member of the Pontifical Academy of Sciences
1988 Wolf Prize in Physics
1989 Prince of Asturias Awards in Concord
1989 Companion of Honour
1999 Julius Edgar Lilienfeld Prize of the American Physical Society[30]
2003 Michelson Morley Award of Case Western Reserve University
2006 Copley Medal of the Royal Society[31]
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