2008/9 Schools Wikipedia Selection. Related subjects: Astronomers and physicists
Stephen William Hawking
|Born|| January 8, 1942
|Fields||Applied Mathematics and Theoretical Physics|
|Institutions||University of Cambridge|
|Alma mater||University of Oxford
University of Cambridge
|Doctoral advisor||Dennis Sciama|
|Doctoral students|| Bruce Allen
|Known for||Black holes
|Notable awards|| Prince of Asturias Award (1989)
Copley Medal (2006)
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, and a Fellow of Gonville and Caius College, Cambridge. 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. His scientific career spans more than 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. Hawking is disabled by amyotrophic lateral sclerosis (ALS), commonly known in the United States as Lou Gehrig's Disease. The illness has progressed over the years and he is now almost completely paralysed.
Stephen William 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 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). 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 he attended St Albans High School for Girls between 1950 to 1953. Unlike today, boys were educated at that time at the Girls school until the age of 10. From the age of 11, he attended St Albans School, where he was a good, but not an exceptional, student. When asked later to name a teacher who had inspired him, Hawking named his Mathematics teacher, " Mr Tahta" . 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. 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." He 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."
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. 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 (colloquially known as Lou Gehrig's disease), a type of 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. Stephen revealed that he did not see much point in obtaining a doctorate if he was to die soon. Hawking later said that the real turning point was his 1965 marriage to Jane Wilde, a language student. After gaining his Ph.D. Stephen became first a Research Fellow, and later on a Professorial Fellow at Gonville and Caius College.
Jane Hawking, née Wilde, Hawking's first wife, with whom he had three children, cared for him until 1991 when the couple separated, reportedly due to the pressures of fame and his increasing disability. Hawking married his nurse Elaine Mason in 1995. (Elaine Mason's first husband, David Mason, had designed the first version of Hawking's talking computer). In October 2006 Hawking filed for divorce.
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. Reportedly, Hawking and his first family were reconciled in 2007.
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. Dr. Hawking is a member of the Board of Sponsors of The Bulletin of the Atomic Scientists.
At the celebration of his 65th birthday on January 8, 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 flight, costing an estimated £100,000. Stephen Hawking's zero-gravity flight of Zero Gravity Corporation, during which he experienced weightlessness eight times, took place on April 26, 2007.
He became the first quadriplegic to float free in a weightless state. This was the first time in 40 years that he moved freely beyond the confines of his wheelchair. The fee is normally $3,750 for 10-15 plunges, but Hawking was not required to pay the fee. Before the flight he was quoted as 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 global warming, 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."
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 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.
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.
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, 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 consistent with a Universe which is not closed also.
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.
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.
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.||”|
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. 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.||”|
—Stephen Hawking, A Brief History of Time (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 is severely disabled by amyotrophic lateral sclerosis, or ALS (a type of motor neurone disease); this condition is 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 the university. Symptoms of the disorder first appeared while he was enrolled at Cambridge. He lost balance and fell down a flight of stairs, 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 gradually lost the use of his arms, legs, and voice, and is now almost completely paralyzed. 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 tracheotomy 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: "Those were the days of atomic gloom and doom, so we all had a rather short life expectancy."
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 and research papers, browse the World Wide Web, and write e-mails. The system also uses radio transmission to provide control over doors in his home and office.
Hawking receives a new computer every 18-24 months donated by Intel. One such computer was donated in April of 2005 and is based on the Centrino chipset. It consists of two pieces, a rear chassis which houses 3 160 Whr batteries and various external peripherals, and a front chassis, which houses a Tablet-PC and the speakers which project his hardware-synthesized voice. The two chassis are connected via a custom-designed umbilical cable which allows power and electrical signals to travel back and forth. Hawking's computer can run for up to 16 hours without needing a recharge.
The computer utilizes a wireless data card that runs on mobile phone networks. This allows Hawking to check his email and browse the web while away from a wireless LAN. Hawking can also make and receive voice phone calls via a mobile phone with an external microphone in front of his computer speakers.
- 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 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. His most recent book, A Briefer History of Time (2005), co-written by Leonard Mlodinow aims to update his earlier works and make them accessible to an even wider audience. He and his daughter, Lucy Hawking, have recently published a children's book focusing on science that has been described to be "like Harry Potter, but without the magic." This book is called George's Secret Key to the Universe and includes information on Hawking Radiation.
- 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 "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.
- Singularities in Collapsing Stars and Expanding Universes with D. W. Sciama, 1969 Comments on Astrophysics and Space Physics Vol 1 #1
- The Nature of Space and Time with Roger Penrose, foreword by Michael Atiyah, New Jersey: Princeton University Press, 1996, ISBN 0-691-05084-8
- The Large Scale Structure of Spacetime with George Ellis, 1973 ISBN 0521099064
- 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 University Press, 2005
- God Created the Integers: The Mathematical Breakthroughs That Changed History, Running Press, 2005 ISBN 0762419229
- A Brief History of Time, (Bantam Press 1988) ISBN 055305340X
- Black Holes and Baby Universes and Other Essays, (Bantam Books 1993) ISBN 0553374117
- The Universe in a Nutshell, (Bantam Press 2001) ISBN 055380202X
- On The Shoulders of Giants. The Great Works of Physics and Astronomy, (Running Press 2002) ISBN 076241698X
- A Briefer History of Time, (Bantam Books 2005) ISBN 0553804367
Footnote: 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.
Films and series
- A Brief History of Time (film)
- Stephen Hawking's Universe
- Hawking's Paradox
- Masters of Science Fiction
Full lists of Hawking's publications are available on his website.
- 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