mercredi 14 mars 2018

Astrophysicist Stephen Hawking passed away










Rest In Peace.

March 14, 2018

British scientist Stephen Hawking is dead, announces a statement from his family.

British theoretical physicist Stephen Hawking died at the age of 76, the British Press Association reported on Tuesday, citing a spokesman for the family. Born in Oxford in the United Kingdom, he died at home in Cambridge.


Image above: Hawking taking a zero-gravity flight in a reduced-gravity aircraft in 2007. Image Credits: Jim Campbell / Aero-News Network.

"We are deeply saddened by the death of our beloved father today." "He was a great scientist and an extraordinary man whose work will live for many years," wrote his children Lucy, Robert and Tim in a text also published by the British agency Press Association.

Nailed in a chair and speaking through a computer, Stephen Hawking devoted his life to unlocking the secrets of the universe and popularizing astrophysics, to the point of becoming a star.

Push the limits

"I'm sure my disability has something to do with my celebrity. People are fascinated by the contrast between my very limited physical abilities and the extremely wide nature of the universe I'm studying, "said the contemporary scientist, certainly the most famous in the world.

Stephen Hawking was born in Oxford on January 8, 1942, 300 years to the day after Galileo's death.

His father, a biologist, wants him to follow his steps by studying medicine in Oxford. But young Stephen has already taken a passion for mathematics. This subject is not taught in the prestigious university, he opts for physics. After three years, he left for Cambridge to pursue research in astronomy.

Charcot's disease

Shortly after his 21st birthday, he learns that he suffers from paralytic degenerative disease, amyotrophic lateral sclerosis (ALS) or Charcot's disease.

Doctors give him only two years to live. Not even knowing if he will be able to complete his doctoral thesis, he is plunged into a deep depression, from which he only comes out thanks to his meeting with a linguistics student, Jane Wilde, whom he married in 1965.

The couple, who divorced 30 years later, will have three children. Stephen Hawking will marry Elaine Mason for the second time, after eleven years in 2006.

His body declines inexorably. In 1974, he was unable to feed himself or get out of bed on his own. In 1985, he definitively lost the use of speech after undergoing tracheotomy following pneumonia.

"Completely understand the universe"

But his mind is intact. And his simple goal: "to completely understand the universe, why he is as he is and why he exists".

In the 1970s, he developed the idea that black holes do not just absorb any matter and light passing near them but also emit radiation, the "Hawking radiation".

In doing so, he is the first to reach out to the grail of physicists: to begin to reconcile the two great theories that explain the functioning of the universe and are apparently incompatible, namely the general relativity of Einstein for the infinitely great and quantum mechanics for the infinitely small.

In the opinion of the scientists, this theory would have earned Stephen Hawking the Nobel Prize if it could have been experimentally demonstrated.

In the footsteps of Newton

At 32, he became the youngest member of the Royal Society, the British equivalent of the Academy of Sciences.

In 1980, he was awarded the Lucasian Chair in Mathematics at Cambridge University, a post he held before him by Isaac Newton. He will leave in 2009, struck by the age limit.

While deepening his work on the origins of the universe, the theorist published in 1988 "A brief history of time," to explain to the general public the great principles of cosmology, the Big Bang to string theory.

Never a book of popular science will be so successful. Since its publication, more than nine million copies have been sold.

Unparalleled communication

Stephen Hawking then becomes the popular incarnation of the scientist, multiplying the interventions to promote the research and, sometimes, to worry about its possible excesses.

Formidable communicator, able to perform a weightless flight despite his disability, he lends himself to the game with a certain pleasure and a great sense of humor. His Facebook page that he feeds himself with messages signed "SH" has more than 4 million "friends".

He plays his own part in series like "Star Trek", "The Big Bang Theory" and "The Simpsons", signs children's books with his daughter Lucy, "sings" with his synthetic voice alongside U2, Pink Floyd and even Monthy Python.

A year ago, he appeared at a conference

Stephen Hawking books:

Popular books

    A Brief History of Time (1988)
    Black Holes and Baby Universes and Other Essays (1993)
    The Universe in a Nutshell (2001)
    On the Shoulders of Giants (2002)
    God Created the Integers: The Mathematical Breakthroughs That Changed History (2005)
    The Dreams That Stuff Is Made of: The Most Astounding Papers of Quantum Physics and How They Shook the Scientific World (2011)
    My Brief History (2013)

Co-authored

    The Nature of Space and Time (with Roger Penrose) (1996)
    The Large, the Small and the Human Mind (with Roger Penrose, Abner Shimony and Nancy Cartwright) (1997)
    The Future of Spacetime (with Kip Thorne, Igor Novikov, Timothy Ferris and introduction by Alan Lightman, Richard H. Price) (2002)
    A Briefer History of Time (with Leonard Mlodinow) (2005)
    The Grand Design (with Leonard Mlodinow) (2010)

Forewords

- Black Holes & Time Warps: Einstein's Outrageous Legacy (Kip Thorne, and introduction by Frederick Seitz) (1994)

Children's fiction

Co-written with his daughter Lucy.

    George's Secret Key to the Universe (2007)
    George's Cosmic Treasure Hunt (2009)
    George and the Big Bang (2011)
    George and the Unbreakable Code (2014)

Films and series

    A Brief History of Time (1992)
    Stephen Hawking's Universe (1997)
    Hawking – BBC television film (2004) starring Benedict Cumberbatch
    Horizon: The Hawking Paradox (2005)
    Masters of Science Fiction (2007)
    Stephen Hawking and the Theory of Everything (2007)
    Stephen Hawking: Master of the Universe (2008)
    Into the Universe with Stephen Hawking (2010)
    Brave New World with Stephen Hawking (2011)
    Stephen Hawking's Grand Design (2012)
    The Big Bang Theory (2012, 2014 and 2017)
    Stephen Hawking: A Brief History of Mine (2013)
    The Theory of Everything – Feature film (2014) starring Eddie Redmayne
    Genius by Stephen Hawking (2016)

Selected academic works

- Hawking, S. W.; Penrose, R. (1970). "The Singularities of Gravitational Collapse and Cosmology". Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 314 (1519): 529–548. Bibcode:1970RSPSA.314..529H. doi:10.1098/rspa.1970.0021.
https://doi.org/10.1098%2Frspa.1970.0021

- Hawking, S. (1971). "Gravitational Radiation from Colliding Black Holes". Physical Review Letters. 26 (21): 1344–1346. Bibcode:1971PhRvL..26.1344H. doi:10.1103/PhysRevLett.26.1344.
http://projecteuclid.org/DPubS?service=UI&version=1.0&verb=Display&handle=euclid.cmp/1103857884
https://doi.org/10.1007%2FBF01877517

- Hawking, S.W. (1972). "Black holes in general relativity". Communications in Mathematical Physics. 25 (2): 152–166. Bibcode:1972CMaPh..25..152H. doi:10.1007/BF01877517.
https://doi.org/10.1038%2F248030a0

- Hawking, S. W. (1974). "Black hole explosions?". Nature. 248 (5443): 30–31. Bibcode:1974Natur.248...30H. doi:10.1038/248030a0.
https://doi.org/10.1038%2F248030a0

- Hawking, S.W. (1982). "The development of irregularities in a single bubble inflationary universe". Physics Letters B. 115 (4): 295–297. Bibcode:1982PhLB..115..295H. doi:10.1016/0370-2693(82)90373-2.
https://doi.org/10.1016%2F0370-2693%2882%2990373-2

- Hartle, J.; Hawking, S. (1983). "Wave function of the Universe". Physical Review D. 28 (12): 2960–2975. Bibcode:1983PhRvD..28.2960H. doi:10.1103/PhysRevD.28.2960.
https://doi.org/10.1103%2FPhysRevD.28.2960

- Hawking, S. (2005). "Information loss in black holes". Physical Review D. 72 (8): 084013. arXiv:hep-th/0507171 Freely accessible. Bibcode:2005PhRvD..72h4013H. doi:10.1103/PhysRevD.72.084013.
https://doi.org/10.1103%2FPhysRevD.72.084013

Stephen Hawking Wikipedia page: https://en.wikipedia.org/wiki/Stephen_Hawking

Image (mentioned), Text, Credits: ATS/AFP/Wikipedia/Orbiter.ch Aerospace/Roland Berga.


R. I. P., Orbiter.ch