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Stephen Hawking

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   CAPTION: Stephen Hawking

   Professor Stephen William Hawking
   Professor Stephen William Hawking
         Born        8 January 1942
                     Oxford, UK
       Residence     UK
      Nationality    British
         Field       Physicist
      Institution    University of Cambridge
      Alma Mater     University of Oxford
                     University of Cambridge
   Doctoral Advisor  Dennis Sciama
   Doctoral Students Bruce Allen
                     Fay Dowker
                     Malcolm Perry
                     Bernard J. Carr
                     Gary Gibbons
       Known for     Black holes
                     Theoretical cosmology
                     Quantum gravity
    Notable Prizes   Copley Medal (2006)
       Religion      Does not believe in a personal God

   Stephen William Hawking, CH, CBE, FRS (born 8 January 1942) is a
   theoretical physicist. Hawking is the Lucasian Professor of Mathematics
   at the University of Cambridge, and a Fellow of Gonville and Caius
   College, Cambridge. He is known for his significant contributions to
   the field of quantum physics, particularly his theories regarding
   theoretical cosmology, quantum gravity, 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 London Sunday Times bestseller list for a
   record-breaking 237 weeks.

   Despite enduring severe disability and, of late, being rendered
   quadriplegic by motor neuron disease (specifically, amyotrophic lateral
   sclerosis, or, " Lou Gehrig's disease"), he has had a successful career
   for many years, and has achieved status as an academic celebrity. He is
   considered by most as one of the greatest scientists of the modern age.

Biography

   Stephen Hawking was born on January 8, 1942, to Frank Hawking, a
   research biologist, and Isobel Hawking. He had two younger sisters,
   Philippa and Mary, and an adopted brother, Edward.

   Though Hawking's parents had their home in North London, they relocated
   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 German air force). 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.

   In 1950, Hawking and his family moved to St Albans in Hertfordshire
   where, from the age of 11, he attended St Albans School, where he was a
   good but not exceptional student. He maintains his connection with the
   school, giving his name to one of the four houses and to an
   extra-curricular 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. He was always interested
   in science, but decided that medicine and biology were "too inexact,
   too descriptive". He enrolled at University College, Oxford with the
   intent of studying mathematics, but after his first year changed his
   concentration to physics. 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." He was popular 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 cleverer than most of themselves."

   After receiving his B.A. degree at Oxford in 1962, he stayed to study
   astronomy, deciding to leave when he found that studying sunspots,
   which was all the observatory was equipped for, didn't appeal to him
   and that he was more interested in theory than in observation. 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 was struck by the motor
   neuron disease which would cost him the loss of 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. Hawking later said that the real turning point was
   his 1965 marriage to Jane Wilde, a language student.

   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. Prof. Hawking is a
   member of the Board of Sponsors of The Bulletin of the Atomic
   Scientists .

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. This led, in 1971,
   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.

   Hawking also suggested that, 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 as Hawking radiation, until they
   exhaust their energy and evaporate.

   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; while one cannot travel North of the North pole, there is
   no boundary there. While originally the no-boundary proposal predicted
   a closed Universe, discussions with Neil Turok led to the realization
   that the no-boundary proposal is consistent with a Universe which is
   not closed also.

Illness

   Hawking is severely disabled by amyotrophic lateral sclerosis, or ALS
   (a type of motor neuron disease commonly known in the United States as
   Lou Gehrig's disease).

   When he was young, he enjoyed riding horses and playing with the other
   children. At Oxford, he coxed a rowing team, which, he stated, helped
   relieve his immense boredom at university. Symptoms of the disorder
   first appeared while he was enrolled at Cambridge. He lost balance and
   fell downstairs, hitting his head. Worried of losing his genius, he
   took the Mensa International test, to verify that his intellectual
   abilities were intact. Diagnosis came when Hawking was 21, shortly
   before his first marriage, and doctors said he would not survive more
   than two or three years. He battled the odds and has survived much
   longer than most sufferers of ALS , although he has become increasingly
   disabled by the gradual progress of the disease.

   He gradually lost the use of his arms, legs, and voice, and is now
   almost completely paralyzed. The computer system attached to his
   wheelchair is operated by Hawking via an infra-red 'blink switch'
   clipped onto his glasses. By scrunching his right cheek up, he is able
   to talk, compose speeches, research papers, browse the World Wide Web
   and write e-mail. The system also uses radio transmission to provide
   control over doors in his home and office.

   During a visit to the research centre CERN in Geneva in 1985, Hawking
   contracted pneumonia, which in his condition was life-threatening. It
   resulted in acute difficulty of breathing, which could only be overcome
   through a tracheostomy by which Stephen Hawking lost his natural speech
   ability. He has since used an electronic voice synthesizer to
   communicate. The voice synthesizer, which has an American accent, is of
   a model that is no longer produced. Asked why he has still kept it
   after so many years, Hawking mentioned that he has not heard a voice he
   likes better and because he identifies with it. Hawking is said to be
   looking for a replacement since, other than being obsolete, the
   synthesizer, a DECtalk DTC01 is now considered large and fragile but as
   of present, finding a software alternative has been difficult. During a
   lecture in Hong Kong in June 2006, he joked that if he got a new one
   with a French accent, his wife would divorce him.

   When Hawking (then using a wheelchair and unable to dress himself) and
   his wife were first living together, they received no outside
   assistance other than from physics students who helped in exchange for
   extra attention with their work. As his condition worsened, Hawking
   needed a team of nurses to provide round-the-clock care. He also needed
   a wheelchair for mobility.

   Despite his disease, he describes himself as "lucky" — not only has the
   slow progress of his disease provided time to make influential
   discoveries, it has also afforded time to have, in his own words, "a
   very attractive family" . 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."

   Hawking's first wife cared for him until 1991 when the couple separated
   under the pressures of fame, his increasing disability, and an affair
   Hawking began with one of his nurses, Elaine Mason. He and Elaine Mason
   were married in 1995. (Elaine Mason's first husband, David Mason, had
   designed the first version of Hawking's talking computer.) In October
   2006, the Hawkings filed for divorce . A 2004 Vanity Fair article by
   Judy Bachrach indicated allegations of violence toward Hawking by his
   second wife, though a police investigation into the matter that same
   year was inconclusive.

   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 Hawking is a novelist. Their son
   Robert Hawking emigrated to the United States, married, and has one
   child, George Edward Hawking.

Distinction

   Hawking's belief that the average person should have access to his work
   led him to write a series of popular science books in addition to his
   academic work. The first of these, A Brief History of Time, was
   published on April 1, 1988 by Hawking, his family and friends, and some
   leading physicists. It became a documentary in 1991. It surprisingly
   became a best-seller and was followed by The Universe in a Nutshell
   (2001).

   Both books have remained highly popular all over the world. A
   collection of essays titled Black Holes and Baby Universes (1993) was
   also popular. He has now written a new book, A Briefer History of Time
   (2005) that aims to update his earlier works and make them accessible
   to a wider audience. He has recently announced that he plans to write a
   children's book focusing on science that has been described to be "like
   Harry Potter, but without the magic."

   Hawking is also known for his wit; he is famous for his oft-made
   statement, "When I hear of Schrödinger's cat, I reach for my pistol."
   This was a deliberately ironic paraphrase of the phrase "Whenever I
   hear the word culture... I release the safety-catch of my Browning",
   from the play Schlageter (Act 1, Scene 1) by German playwright and Nazi
   Poet Laureate, Hanns Johst.

   His wit has both entertained the non-specialist public and helped them
   to understand complex questions. Asked in October 2005 on the British
   daytime chat show Richard & Judy, to explain his assertion that the
   question "What came before the Big Bang?" was meaningless, he compared
   it to asking "What lies north of the north pole?"

   Hawking is an active supporter of various causes. He appeared on a
   political broadcast for the United Kingdom's Labour Party, and actively
   supports the children's charity SOS Children's Villages UK.

   He recently made the news for announcing that he believes colonization
   on other planets and/or the moon is imperative to ensure the
   continuation of the human race.

Comments on global warming

   In the third week of June 2006, Stephen Hawking spoke in China and made
   the statement that humans might have already fried the atmosphere and
   inadvertently reconnected the planet Earth with her dead neighbours.

   The China Daily asked Hawking about the environment, and he responded
   that he was "very worried about global warming." He said he was afraid
   that Earth "might end up like Venus, at 250 degrees Celsius and raining
   sulfuric acid." In the light of this discussion Hawking asked an open
   question on Yahoo Answers "How can the human race survive the next
   hundred years?" and received well over 25,000 responses . The validity
   of the question was confirmed by Hawking himself and the Yahoo Answers
   staff. An answer has already been chosen.

   In an ABC News interview in August 2006, Hawking explained, "The danger
   is that global warming may become self-sustaining, if it has not done
   so already. The melting of the Arctic and Antarctic ice caps reduces
   the fraction of solar energy reflected back into space, and so
   increases the temperature further. Climate change may kill off the
   Amazon and other rain forests, and so eliminate one of the main ways in
   which carbon dioxide is removed from the atmosphere. The rise in sea
   temperature may trigger the release of large quantities of carbon
   dioxide, trapped as hydrides on the ocean floor. Both these phenomena
   would increase the greenhouse effect, and so further global warming. We
   have to reverse global warming urgently, if we still can."

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 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.

   Another 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." (1988) According to the
   updated 10th anniversary edition of A Brief History of Time, Hawking
   has conceded the bet "to the outrage of Kip's liberated wife" due to
   subsequent observational data in favour of black holes.

   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, 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 favour, awarding him Total Baseball, The Ultimate
   Baseball Encyclopedia. However, Thorne remains unconvinced of Hawking's
   proof and declined to contribute to the award.

Selected publications

Technical

     * The Large Scale Structure of Spacetime with George Ellis, 1973
     * The Large, the Small, and the Human Mind, (with Abner Shimony,
       Nancy Cartwright, and Roger Penrose), Cambridge University Press,
       1997, ISBN 0-521-56330-5 (hardback), ISBN 0-521-65538-2
       (paperback), Canto edition: ISBN 0-521-78572-3
     * Information Loss in Black Holes, Cambridge 2005

Popular

     * A Brief History of Time, (Bantam Press 1988)
     * Black Holes and Baby Universes and Other Essays, (Bantam Books
       1993)
     * The Universe in a Nutshell, (Bantam Press 2001)
     * On The Shoulders of Giants. The Great Works of Physics and
       Astronomy, (Running Press 2002)
     * A Briefer History of Time, (Bantam Books 2005)

   Foot note On Hawking's website, he denounces the unauthorised
   publication of The Theory of Everything and asks consumers to be aware
   that he was not involved in its creation.

   Full lists of Hawking's publications are available on his website.

Awards

     * 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
     * 2003 Michelson Morley Award of Case Western Reserve University
     * 2006 Copley Medal of the Royal Society

Popular culture

List of former students

   Fay Dowker      1987–1990
   Bruce Allen     1980–1983
   Alan Yuille     1977–1981
   Malcolm Perry   1974–1978
   Bernard J. Carr 1972–1975
   Gary Gibbons    1970–1972

   Further information about Hawking's former students may be found in the
   Mathematical Genealogy Project.

Quotes

     * Even if there is only one possible unified theory, it is just a set
       of rules and equations. What is it that breathes fire into the
       equations and makes a universe for them to describe?
     * I think computer viruses should count as life. I think it says
       something about human nature that the only form of life we have
       created so far is purely destructive. We've created life in our own
       image.
     * It is not clear that intelligence has any long-term survival value.
     * My goal is simple. It is a complete understanding of the universe,
       why it is as it is and why it exists at all
     * Not only does God play dice, but... he sometimes throws them where
       they cannot be seen.
     * Someone told me that each equation I included in the book would
       halve the sales.
     * The usual approach of science of constructing a mathematical model
       cannot answer the questions of why there should be a universe for
       the model to describe. Why does the universe go to all the bother
       of existing?
     * The whole history of science has been the gradual realisation that
       events do not happen in an arbitrary manner, but that they reflect
       a certain underlying order, which may or may not be divinely
       inspired.
     * There are grounds for cautious optimism that we may now be near the
       end of the search for the ultimate laws of nature.
     * To confine our attention to terrestrial matters would be to limit
       the human spirit.
     * We are just an advanced breed of monkeys on a minor planet of a
       very average star. But we can understand the Universe. That makes
       us something very special.
     * (While looking at the Warp core on the set of Star Trek: The Next
       Generation) I'm working on that.
     * For millions of years mankind lived just like the animals. Then
       something happened which unleashed the power of our imagination. We
       learned to talk. (Also used by Pink Floyd on the song Keep Talking
       from the album The Division Bell.)
     * It was my idea.
     * When I hear of Schrödinger's cat, I reach for my gun.
     * Personally, I prefer the Simpsons
     * I call it a "Hawking Hole". (From his voiceover cameo on the
       television show Futurama; he is describing a tear in the fabric of
       space-time that the protagonist Philip J. Fry had originally dubbed
       a "Fry Hole". )
     * I call it a "Hawking Chamber". (Spoken later in the same Futurama
       episode in reference to a cryogenic freezing chamber he obviously
       had not invented.)

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