The Big Bang Theory Stephen Hawking 1942-2018.
The Big Bang Theory Stephen Hawking 1942-2018.
Known worldwide for his contributions to theoretical physics and cosmology and for his popular-science writings, Stephen William Hawking was born in Oxford on 8 January 1942 to Frank and Isobel Hawking and grew up in Highgate, hire ci developer London and St Albans, Hertfordshire.
He was educated at St Albans School and at University College, Oxford. Despite his father’s wish for him to study medicine, Hawking opted for physics and chemistry, beginning his undergraduate studies in 1959, aged 17.
Initially bored and lonely at university, Hawking fared better after joining the boat club, in which he coxed a rowing team. He found his academic studies easy but didn’t work especially hard, and fell on the boundary between first- and second-class degrees, ultimately being awarded the former following a viva.
He began his doctoral training in cosmology at Cambridge under Dennis Sciama in 1962 but was diagnosed with motor neuron disease the following year. Dedicated php developers Doctors’ estimates that Hawking had only two years to live proved to be wrong, and after an initial depression over his illness he both returned to work and married Jane Wilde, a friend of his sister’s whom Hawking had met shortly before his illness was diagnosed.
At Cambridge, Hawking and his colleague Roger Penrose developed new mathematical tools for use in Einstein’s general relativity. Using these, they showed that singularities – points of infinite density and energy such as those thought to be at the center of black holes – are a common feature of the theory, and that, if the effects of quantum mechanics are ignored, the universe must also have begun at such a point.
In 1969, Hawking was made a fellow of Gonville and Caius College, and subsequently began the work on black holes for which he is perhaps best known among physicists. He did, however, make a bet with Caltech’s Kip Thorne that the X-ray source Cygnus X-1 was not a black hole, which Hawking considered an insurance policy against his work is incorrect, and which would be the first of a number of friendly wagers made with colleagues. (He conceded the bet in 1990.)
In 1970, Hawking mathematically proved a theorem of John Wheeler’s that any black hole can be completely described by just three properties – its mass, angular momentum, and electric charge.
The second law of thermodynamics says that the amount of entropy in a system will always increase. As entropy is a measure of disorder, it would be possible to decrease the total entropy in the universe simply by throwing mass into a black hole.
Hawking’s discovery that the area of a black hole also never decreases led Jacob Bekenstein to suggest that in some way the area is the entropy of the black hole. The problem with this was that if a black hole has entropy then it must have a temperature, and must, therefore, radiate heat – so it would no longer be black.
In 1974, Hawking showed that black holes will, in fact, do precisely this through what is now known as Hawking radiation, which arises due to quantum fluctuations at the black hole’s event horizon. Space, generally considered to be empty, is actually filled with pairs of virtual particles popping into and out of existence, and whereas they would normally vanish more or less instantly, in this case, for each pair, one is trapped by the black hole and the other escapes.
If enough time passes, black holes will radiate away all their energy and completely evaporate. The lifetime of a black hole is proportional to the cube of its mass – for a solar-mass black hole, it would be around 1067 years.
Hawking then turned his professional attention back to the universe as a whole. In 1983, along with Jim Hartle of the University of California, Santa Barbara, he developed a cosmological model in which the universe has no boundary in spacetime – overturning his own earlier theory that it must have begun with a singularity.
In 1985, Hawking contracted pneumonia during a visit to CERN, and, following an emergency tracheotomy, lost the remainder of his ability to speak. A donation of speech-synthesis software from American company Words Plus the following year restored Hawking’s ability to communicate independently – albeit painstakingly slowly – and gave him the computerized voice that would be instantly identifiable for the remainder of his life.
Hawking had begun to work on a popular-science book in 1982 with an eye to funding his children’s education and his own home care, and A Brief History of Time was published by Bantam Press in 1988. laravel developers uk It would remain on the Sunday Times bestseller list for an unprecedented four years and sell more than nine million copies – and make its author famous way beyond the world of cosmology. A collection of essays, Black Holes, and Baby Universes, would follow in 1993, and a television series, Stephen Hawking’s Universe, in 1997. Hawking also made a number of TV appearances as himself, including in Star Trek: The Next Generation, The Simpsons, and The Big Bang Theory.
Hawking had a public debate with Peter Higgs in 2008 after claiming – and betting – that the Higgs boson would never be found, but quickly acknowledged that he’d been wrong after its discovery at CERN in 2012. He retired from the Lucasian professorship in 2009 owing to a university policy that prevents holders retaining the chair past the age of 67.
During his career, Hawking – an Honorary Fellow of the Institute of Physics (IOP) – was honoured with a number of awards, including IOP’s first Dirac Medal in 1987, the Royal Astronomical Society’s Gold Medal, the Wolf Prize, the Royal Society’s Copley Medal, and the United States’ highest civilian honour, the Presidential Medal of Freedom. He was made a CBE in 1982 and appointed as a member of the Order of Companions of Honour in 1989.