Stephen William Hawking CH, CBE, FRS, FRSA (Listeni/ˈstiːvən ˈhɔːkɪŋ/; born 8 January 1942) is a British theoretical physicist, cosmologist, author and Director of Research at the Centre for Theoretical Cosmology within the University of Cambridge.His scientific works include a collaboration with Roger Penrose on gravitational singularity theorems in the framework of general relativity, and the theoretical prediction that black holes emit radiation, often called Hawking radiation. Hawking was the first to set forth a theory of cosmology explained by a union of the general theory of relativity and quantum mechanics. He is a vigorous supporter of the many-worlds interpretation of quantum mechanics.
He is an Honorary Fellow of the Royal Society of Arts, a lifetime member of the Pontifical Academy of Sciences, and a recipient of the Presidential Medal of Freedom, the highest civilian award in the United States. Hawking was the Lucasian Professor of Mathematics at the University of Cambridge between 1979 and 2009 and has achieved commercial success with works of popular science in which he discusses his own theories and cosmology in general; his book A Brief History of Time stayed on the British Sunday Times best-seller list for a record-breaking 237 weeks.
ALS, or amyotrophic lateral sclerosis, is a progressive neurodegenerative disease that affects nerve cells in the brain and the spinal cord. A-myo-trophic comes from the Greek language. “A” means no. “Myo” refers to muscle, and “Trophic” means nourishment – “No muscle nourishment.” When a muscle has no nourishment, it “atrophies” or wastes away. “Lateral” identifies the areas in a person’s spinal cord where portions of the nerve cells that signal and control the muscles are located. As this area degenerates it leads to scarring or hardening in the region.
Motor neurons reach from the brain to the spinal cord and from the spinal cord to the muscles throughout the body. The progressive degeneration of the motor neurons in ALS eventually leads to their demise. When the motor neurons die, the ability of the brain to initiate and control muscle movement is lost. With voluntary muscle action progressively affected, people may lose the ability to speak, eat, move and breathe. The motor nerves that are affected when you have ALS are the motor neurons that provide voluntary movements and muscle control. Examples of voluntary movements are making the effort to reach for a smart phone or step off a curb. These actions are controlled by the muscles in the arms and legs.
There are two different types of ALS, sporadic and familial. Sporadic which is the most common form of the disease in the U.S., is 90 – 95 percent of all cases. It may affect anyone, anywhere. Familial ALS accounts for 5 to 10 percent of all cases in the U.S. Familial ALS means the disease is inherited. In those families, there is a 50% chance each offspring will inherit the gene mutation and may develop the disease. French neurologist Jean-Martin Charcot discovered the disease in 1869.
Primary and secondary
Hawking began his schooling at the Byron House School; he later blamed its “progressive methods” for his failure to learn to read while at the school. In St Albans, the eight-year-old Hawking attended St Albans High School for Girls for a few months; at that time, younger boys could attend one of the houses.
He attended Radlett School for a year and from September 1952, St Albans School.The family placed a high value on education. Hawking’s father wanted his son to attend the well-regarded Westminster School, but the 13-year-old Hawking was ill on the day of the scholarship examination. His family could not afford the school fees without the financial aid of a scholarship, so Hawking remained at St Albans. A positive consequence was that Hawking remained with a close group of friends with whom he enjoyed board games, the manufacture of fireworks, model aeroplanes and boats, and long discussions about Christianity and extrasensory perception.From 1958, and with the help of the mathematics teacher Dikran Tahta, they built a computer from clock parts, an old telephone switchboard and other recycled components.Although at school he was known as “Einstein”, Hawking was not initially successful academically. With time, he began to show considerable aptitude for scientific subjects, and inspired by Tahta, decided to study mathematics at university. Hawking’s father advised him to study medicine, concerned that there were few jobs for mathematics graduates. He wanted Hawking to attend University College, Oxford, his own alma mater. As it was not possible to read mathematics there at the time, Hawking decided to study physics and chemistry. Despite his headmaster’s advice to wait until the next year, Hawking was awarded a scholarship after taking the examinations in March 1959.
Undergraduate
Hawking began his university education at the University College, Oxford in October 1959 at the age of 17.For the first 18 months, he was bored and lonely: he was younger than many other students, and found the academic work “ridiculously easy”.His physics tutor, Robert Berman, later said, “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.”A change occurred during his second and third year when, according to Berman, Hawking made more effort “to be one of the boys”. He developed into a popular, lively and witty college member, interested in classical music and science fiction. Part of the transformation resulted from his decision to join the college Boat Club, where he coxed a rowing team.The rowing trainer at the time noted that Hawking cultivated a daredevil image, steering his crew on risky courses that led to damaged boats.
Hawking has estimated that he studied about a thousand hours during his three years at Oxford. These unimpressive study habits made sitting his finals a challenge, and he decided to answer only theoretical physics questions rather than those requiring factual knowledge. A first-class honours degree was a condition of acceptance for his planned graduate study in cosmology at the University of Cambridge.Anxious, he slept poorly the night before the examinations, and the final result was on the borderline between first- and second-class honours, making a viva (oral examination) necessary.Hawking was concerned that he was viewed as a lazy and difficult student, so when asked at the oral to describe his future plans, he said, “If you award me a First, I will go to Cambridge. If I receive a Second, I shall stay in Oxford, so I expect you will give me a First.”He was held in higher regard than he believed: as Berman commented, the examiners “were intelligent enough to realise they were talking to someone far cleverer than most of themselves”. After receiving a first-class BA (Hons.) degree, and following a trip to Iran with a friend, he began his graduate work at Trinity Hall, Cambridge, in October 1962.
Graduate
Hawking’s first year as a doctoral student was difficult. He was initially disappointed to find that he had been assigned Dennis William Sciama, one of the founders of modern cosmology, as a supervisor rather than noted astronomer Fred Hoyle, and he found his training in mathematics inadequate for work in general relativity and cosmology.After being diagnosed with motor-neuron disease, Hawking fell into a depression; though his doctors advised that he continue with his studies, he felt there was little point.However, his disease progressed more slowly than doctors had predicted. Although Hawking had difficulty walking unsupported and his speech was almost unintelligible, an initial diagnosis that he had only two years to live proved unfounded. With the encouragement of Sciama, he returned to his work.Hawking started developing a reputation for brilliance and brashness when he publicly challenged the work of Fred Hoyle and his student Jayant Narlikar at a lecture in June 1964
When Hawking began his graduate studies, there was much debate in the physics community about the prevailing theories of the creation of the Universe: the Big Bang and the Steady State theories.Inspired by Roger Penrose’s theorem of a spacetime singularity in the centre of black holes, Hawking applied the same thinking to the entire universe, and during 1965 wrote his thesis on this topic.There were other positive developments: Hawking received a research fellowship at Gonville and Caius College.He obtained his PhD degree in cosmology in March 1966,and his essay entitled “Singularities and the Geometry of Space-Time” shared top honours with one by Penrose to win that year’s prestigious Adams Prize.
In March 1968, Hawking marched alongside Tariq Ali and Vanessa Redgrave to protest against the Vietnam War. He is a longstanding Labour Party supporter. He recorded a tribute for the 2000 Democratic presidential candidate Al Gore, called the 2003 invasion of Iraq a “war crime”,boycotted a conference in Israel because of concerns about Israel’s policies towards Palestinians,campaigned for nuclear disarmament, and has supported stem cell research, universal health care,and action to prevent climate change. In August 2014, Hawking was one of 200 signatories to a letter opposing Scottish independence in the run-up to September’s referendum on that issue.
Hawking has received numerous awards and honours. Already early in the list, in 1974 he was elected a Fellow of the Royal Society At that time, his nomination read:
“Hawking has made major contributions to the field of general relativity. These derive from a deep understanding of what is relevant to physics and astronomy, and especially from a mastery of wholly new mathematical techniques. Following the pioneering work of Penrose he established, partly alone and partly in collaboration with Penrose, a series of successively stronger theorems establishing the fundamental result that all realistic cosmological models must possess singularities. Using similar techniques, Hawking has proved the basic theorems on the laws governing black holes: that stationary solutions of Einstein’s equations with smooth event horizons must necessarily be axisymmetric; and that in the evolution and interaction of black holes, the total surface area of the event horizons must increase. In collaboration with G. Ellis, Hawking is the author of an impressive and original treatise on “Space-time in the Large”.
The citation continues:”Other important work by Hawking relates to the interpretation of cosmological observations and to the design of gravitational wave detectors.”
1966–1975
In his work, and in collaboration with Penrose, Hawking extended the singularity theorem concepts first explored in his doctoral thesis. This included not only the existence of singularities but also the theory that the Universe might have started as a singularity. Their joint essay was the runner-up in the 1968 Gravity Research Foundation competition. In 1970 they published a proof that if the Universe obeys the general theory of relativity and fits any of the models of physical cosmology developed by Alexander Friedmann, then it must have begun as a singularity.In 1969, Hawking accepted a specially created Fellowship for Distinction in Science to remain at Caius.
In 1970, Hawking postulated what became known as the second law of black hole dynamics, that the event horizon of a black hole can never get smaller. With James M. Bardeen and Brandon Carter, he proposed the four laws of black hole mechanics, drawing an analogy with thermodynamics. To Hawking’s irritation, Jacob Bekenstein, a graduate student of John Wheeler, went further—and ultimately correctly—to apply thermodynamic concepts literally In the early 1970s, Hawking’s work with Carter, Werner Israel and David C. Robinson strongly supported Wheeler’s no-hair theorem that no matter what the original material from which a black hole is created it can be completely described by the properties of mass, electrical charge and rotation. His essay titled “Black Holes” won the Gravity Research Foundation Award in January 1971. Hawking’s first book, The Large Scale Structure of Space-Time, written with George Ellis, was published in 1973.
Beginning in 1973, Hawking moved into the study of quantum gravity and quantum mechanics. His work in this area was spurred by a visit to Moscow and discussions with Yakov Borisovich Zel’dovich and Alexei Starobinsky, whose work showed that according to the uncertainty principle rotating black holes emit particles.To Hawking’s annoyance, his much-checked calculations produced findings that contradicted his second law, which claimed black holes could never get smaller,and supported Bekenstein’s reasoning about their entropy.His results, which Hawking presented from 1974, showed that black holes emit radiation, known today as Hawking radiation, which may continue until they exhaust their energy and evaporate.Initially, Hawking radiation was controversial. However, by the late 1970s and following the publication of further research, the discovery was widely accepted as a significant breakthrough in theoretical physics. In March 1974, a few weeks after the announcement of Hawking radiation, Hawking was invested as a Fellow of the Royal Society, one of the youngest scientists to be so honoured.
Hawking was appointed to the Sherman Fairchild Distinguished visiting professorship at the California Institute of Technology (Caltech) in 1970. He worked with a friend on the faculty, Kip Thorne, and engaged him in a scientific wager about whether the dark star Cygnus X-1 was a black hole. The wager was a surprising “insurance policy” against the proposition that black holes did not exist.Hawking acknowledged that he had lost the bet in 1990, which was the first of several that he was to make with Thorne and others.Hawking has maintained ties to Caltech, spending a month there almost every year since this first visit.
1975–1990
Hawking returned to Cambridge in 1975 to a more advanced academic senior position —as reader. The mid- to late 1970s were a period of growing public interest in black holes and of the physicists who were studying them. Hawking was regularly interviewed for print and television. He also received increasing academic recognition of his work.In 1975, he was awarded both the Eddington Medal and the Pius XI Gold Medal, and in 1976 the Dannie Heineman Prize, the Maxwell Prize and the Hughes Medal.Hawking was appointed a professor with a chair in gravitational physics in 1977. The following year he received the Albert Einstein Medal and an honorary doctorate from the University of Oxford.
In the late 1970s, Hawking was elected Lucasian Professor of Mathematics at the University of Cambridge. His inaugural lecture as Lucasian Professor of Mathematics was titled: “Is the end in sight for Theoretical Physics” and proposed N=8 Supergravity as the leading theory to solve many of the outstanding problems physicists were studying.Hawking’s promotion coincided with a health crisis which led to Hawking accepting, albeit reluctantly, some nursing services at home.At the same time, he was also making a transition in his approach to physics, becoming more intuitive and speculative rather than insisting on mathematical proofs. “I would rather be right than rigorous”, he told Kip Thorne In 1981, he proposed that information in a black hole is irretrievably lost when a black hole evaporates. This information paradox violates the fundamental tenet of quantum mechanics, and led to years of debate, including “the Black Hole War” with Leonard Susskind and Gerard ‘t Hooft.
Cosmological inflation—a theory proposing that following the Big Bang the Universe initially expanded incredibly rapidly before settling down to a slower expansion—was proposed by Alan Guth and also developed by Andrei Linde.Following a conference in Moscow in October 1981, Hawking and Gary Gibbons organized a three-week Nuffield Workshop in the summer of 1982 on the Very Early Universe at Cambridge University, which focused mainly on inflation theory.Hawking also began a new line of quantum theory research into the origin of the Universe. In 1981 at a Vatican conference, he presented work suggesting that there might be no boundary—or beginning or ending—to the Universe.He subsequently developed the research in collaboration with Jim Hartle, and in 1983 they published a model, known as the Hartle–Hawking state. It proposed that prior to the Planck epoch, the universe had no boundary in space-time; before the Big Bang, time did not exist and the concept of the beginning of the Universe is meaningless. The initial singularity of the classical Big Bang models was replaced with a region akin to the North Pole. One cannot travel north of the North Pole, but there is no boundary there—it is simply the point where all north-running lines meet and end.Initially the no-boundary proposal predicted a closed universe which had implications about the existence of God. As Hawking explained “If the universe has no boundaries but is self-contained… then God would not have had any freedom to choose how the universe began.”
Hawking did not rule out the existence of a Creator, asking in A Brief History of Time “Is the unified theory so compelling that it brings about its own existence?”In his early work, Hawking spoke of God in a metaphorical sense. In A Brief History of Time he wrote: “If we discover a complete theory, it would be the ultimate triumph of human reason—for then we should know the mind of God.” In the same book he suggested the existence of God was unnecessary to explain the origin of the Universe. Later discussions with Neil Turok led to the realisation that it is also compatible with an open universe.
Further work by Hawking in the area of arrows of time led to the 1985 publication of a paper theorising that if the no-boundary proposition were correct, then when the Universe stopped expanding and eventually collapsed, time would run backwards.A paper by Don Page and independent calculations by Raymond Laflamme led Hawking to withdraw this concept.Honours continued to be awarded: in 1981 he was awarded the American Franklin Medal,and in 1982 made a Commander of the Order of the British Empire Awards do not pay the bills, however, and motivated by the need to finance the children’s education and home expenses, in 1982 Hawking determined to write a popular book about the Universe that would be accessible to the general public.Instead of publishing with an academic press, he signed a contract with Bantam Books, a mass market publisher, and received a large advance for his book. A first draft of the book, called A Brief History of Time, was completed in 1984.
One of the first messages Hawking produced with his speech-generating device was a request for his assistant to help him finish writing A Brief History of Time.[68] Peter Guzzardi, his editor at Bantam, pushed him to explain his ideas clearly in non-technical language, a process that required multiple revisions from an increasingly irritated Hawking. The book was published in April 1988 in the US and in June in the UK, and proved to be an extraordinary success, rising quickly to the top of bestseller lists in both countries and remaining there for months.The book was translated into multiple languages,and ultimately sold an estimated 9 million copies. Media attention was intense,and Newsweek magazine cover and a television special both described him as “Master of the Universe” Success led to significant financial rewards, but also the challenges of celebrity status.Hawking travelled extensively to promote his work, and enjoyed partying and dancing into the small hours. He had difficulty refusing the invitations and visitors which left limited time for work and his students. Some colleagues were resentful of the attention Hawking received, feeling it was due to his disabilityHe received further academic recognition, including five further honorary degrees, the Gold Medal of the Royal Astronomical Society he Paul Dirac Medal and, jointly with Penrose, the prestigious Wolf Prize, he was appointed Member of the Order of the Companions of Honour He reportedly declined a knighthood.
1990–2000
Hawking pursued his work in physics: in 1993 he co-edited a book on Euclidean quantum gravity with Gary Gibbons and published a collected edition of his own articles on black holes and the Big Bang. In 1994 at Cambridge’s Newton Institute, Hawking and Penrose delivered a series of six lectures, which were published in 1996 as “The Nature of Space and Time”. In 1997 he conceded a 1991 public scientific wager made with Kip Thorne and John Preskill of Caltech. Hawking had bet that Penrose’s proposal of a “cosmic censorship conjecture”—that there could be no “naked singularities” unclothed within a horizon—was correct.After discovering his concession might have been premature, a new, more refined, wager was made. This specified that such singularities would occur without extra conditions. The same year, Thorne, Hawking and Preskill made another bet, this time concerning the black hole information paradox.Thorne and Hawking argued that since general relativity made it impossible for black holes to radiate and lose information, the mass-energy and information carried by Hawking radiation must be “new”, and not from inside the black hole event horizon. Since this contradicted the quantum mechanics of microcausality, quantum mechanics theory would need to be rewritten. Preskill argued the opposite, that since quantum mechanics suggests that the information emitted by a black hole relates to information that fell in at an earlier time, the concept of black holes given by general relativity must be modified in some way.
Hawking also maintained his public profile, including bringing science to a wider audience. A film version of A Brief History of Time, directed by Errol Morris and produced by Steven Spielberg, premiered in 1992. Hawking had wanted the film to be scientific rather than biographical, but he was persuaded otherwise. The film, while a critical success, was however not widely released. A popular-level collection of essays, interviews and talk titled Black Holes and Baby Universes and Other Essays was published in 1993and six-part television series Stephen Hawking’s Universe and companion book appeared in 1997. As Hawking insisted, this time the focus was entirely on science.
Recent Comments