Stephen William Hawking, born January 8, 1942 in Oxford, is a physicist British theorist and cosmologist well known for his work on black holes, the cosmology quantum and its popular books on the same subjects. This is his bestseller A brief history of time (A Brief History of Time), which remained on the list of best-selling records in the Sunday Times for 237 consecutive weeks, which made him known to the general public.
Hawking’s media fame also comes from the fact that he performed his work while suffering from a neuromuscular dystrophy attributed to a sclerosis amyotrophic lateral (SLA). This terrible disease, colloquially known in the United States as Lou Gehrig’s disease and in France Charcot’s disease, which leads to complete paralysis and death within a few years usually, broke out in his home shortly after his 20s.
A video uploaded by the University of Cambridge in honor of Stephen Hawking. To obtain a fairly accurate French translation, click on the white rectangle at the bottom right. The English subtitles should then appear. Then click on the nut to the right of the rectangle, then on “Subtitles” and finally on “Translate automatically”. Choose “French”. © Cambridge University
From singularities in cosmology to the radiation of black holes
He was then a student at Cambridge, where he intended to deepen cosmology with Fred Hoyle, one of the most important astrophysicists 1950s and 1960s and co-author of standard model in cosmology of the time, with a universe in eternal and infinite expansion. To his dismay (but it was actually luck as Hawking understood in retrospect), he was assigned as thesis supervisor William Dennis Sciama, relatively unknown at the time. Stimulated by his meeting and his marriage to Jane Wilde in 1965, and because his disease was progressing more slowly than expected, Hawking finished his doctorate by publishing from 1966 onwards resounding articles on the occurrence of singularities in relativistic cosmology. He took up the geometric methods of the great mathematician Roger penrose, which he had initially used to demonstrate the existence of a singularity during the formation of a black hole in general relativity classic.
Hawking’s work came as the discoveries of quasars and especially of fossil radiation by Penzias and Wilson in 1965 had just refuted the theory of stationary cosmology of Hoyle, Hermann Bondi and Thomas Gold. The theory of big Bang of Georges lemaître, Georges Gamow and Ralph alpher was finally going to be taken seriously.
Using Penrose’s mathematical methods and understanding the importance of the ideas of John wheeler on the black holes, wormholes and quantum cosmology, Hawking will deeply mark the physical theory and cosmology during the 1970s and 1980s. Influenced by the work of Bekenstein, Zel’dovich, Starobinsky and Linde, he will make a name for himself by discovering the radiation of black holes in 1974 and by developing several important aspects of the theory of inflation during the 1980s. All this work will lead him to develop a fascinating cosmological model in 1983, universally known today as Hartle-Hawking model. Using the method of calculation in quantum theory known as the path integral of Feynman, whose effectiveness he had seen in his research onentropy and the radiation of black holes, Hawking proposed with Hartle a cosmological model finite in space and characterized by the appearance of imaginary time at the moment when the universe was dominated by the effects of quantum gravity, i.e. before planck time.
From the entropy of black holes to the Higgs boson
We measure all the determination and intellectual capacities of Stephen Hawking when we know that this work was carried out in 1974, when due to the paralysis caused by ALS, he had become unable to eat or get out of bed by himself and that his condition would continue to worsen. His speech, already greatly altered by his illness, so that only people who knew him well could still understand him, gave way to a total inability to speak in 1985. He then contracted a pneumonia, and the doctors had to give him a tracheostomy to save his life. Since the end of the 1980s, he has had to use a computer to talk.
In the late 1990s and early 2000s, Hawking became a staunch supporter of the superstring theory, and in particular the theory M, because it allows us to better understand the origin ofentropy black holes. He will also publish a new popularization book on these subjects in 2001, The universe in a nutshell. The book popularizes theories like the supergravity, the supersymmetry and quantum theory underpinning M theory, the holography and duality of p-branes contained in superstring theory and their implications for black holes and the existence of multiple universes. Scientifically speaking, the M theory convinced Hawking that he had lost his bet on the famous and deep information paradox appearing with the black holes and that he was the first to report. He conceded in 2004 to John Preskill that information is not destroyed in black holes. In 2012, he also conceded Gordon Kane as the higgs boson did exist.
A career hailed by numerous distinctions
In 2009, Hawking left the prestigious Lucasian Chair of Mathematics at Cambridge University, as expected due to the age limit. It has been occupied by great names in physics, including those whose theories have profoundly changed our view of the world: Isaac newton and Paul Dirac. Currently it is Michael green who is the holder.
Holder of numerous awards, Stephen Hawking has not received a Nobel Prize, however, possibly because his work is too theoretical. But he could logically have received the Nobel Prize in physics if we had detected evaporating black holes, for example in LHC. However, he received three million dollars in 2012 as the winner of the Special Prize of the Fundamental Physics Prize Foundation. One of his biggest dreams was to fly in space, when he once made a flight in weightlessness in 2007 thanks to the company Zero-G, founded by Peter Diamandis.
Very involved in the media, he strongly participated in the communication of science to the public. A Stephen Hawking Medal for Science Communication was created in 2016 to recognize contributions of this type. L’asteroid (7672) was also named in his honor. Moreover, in recent years, he has alerted the world against the climate change.
Stephen Hawking is deceased on March 14, 2018, in Cambridge, UK, at the age of 76. A biographical film released in 2014, titled A wonderful history of time, retraces the life of this great physicist.
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