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John Archibald Wheeler

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John Archibald Wheeler
Born(1911-07-09)July 9, 1911
Jacksonville, Florida, USA
DiedApril 13, 2008(2008-04-13) (aged 96)
Hightstown, New Jersey, USA
NationalityAmerican
Alma materJohns Hopkins University
Known forCoining the term 'black hole'
Nuclear fission
Geometrodynamics
General relativity
Unified field theory
AwardsEnrico Fermi Award (1968)
Oersted Medal (1983)
Albert Einstein Medal (1988)
Matteucci Medal (1993)
Wolf Prize (1997)
Scientific career
FieldsPhysics
InstitutionsUniversity of North Carolina
Princeton University
University of Texas at Austin
Doctoral advisorKarl Herzfeld
Doctoral studentsRichard Feynman
Demetrios Christodoulou
Claudio Bunster
Roberto Bruno
Jacob Bekenstein
Robert Geroch
John R. Klauder
Charles Misner
Kip Thorne
Arthur Wightman
Warner A. Miller
Hugh Everett
Bill Unruh
Robert Wald
Milton Plesset
Yavuz Nutku
Arkady Kheyfets
Edward Fireman
David Kerlick

John Archibald Wheeler (July 9, 1911 – April 13, 2008) was an eminent American theoretical physicist. One of the later collaborators of Albert Einstein, he tried to achieve Einstein's vision of a unified field theory. He is also known for having coined the terms black hole and wormhole and the phrase "it from bit".

Early life and education

John Archibald Wheeler was born in Jacksonville, Florida. He graduated from the Baltimore City College high school in 1926[1] and received his doctorate from Johns Hopkins University in 1933. His dissertation, under the supervision of Karl Herzfeld, was on the theory of the dispersion and absorption of helium.

Career in physics

He was a professor of physics at Princeton University from 1938 until 1976 and the director of the Center for Theoretical Physics at the University of Texas at Austin from 1976 to 1986. At the time of his death, he had returned to Princeton as a professor emeritus. Professor Wheeler's graduate students include Richard Feynman, Kip Thorne, and Hugh Everett. Unlike some scholars, he gave a high priority to teaching. Even after he had achieved fame, he continued to teach freshman and sophomore physics, saying that the young minds were the most important.

Wheeler made important contributions to theoretical physics. In 1937, he introduced the S-matrix, which became an indispensable tool in particle physics. He was a pioneer in the theory of nuclear fission, along with Niels Bohr and Enrico Fermi. In 1939, he collaborated with Bohr on the liquid drop model of nuclear fission. Together with many other leading physicists, during World War II, Wheeler interrupted his academic career to participate in the development of the U.S. atomic bomb under the Manhattan Project at the Hanford site, where reactors were constructed to produce the chemical element plutonium for atomic bombs. Even before the Hanford site started up the B-Pile (the first of three reactors), he had anticipated that the accumulation of "fission product poisons" would eventually impede the ongoing nuclear chain reaction by absorbing neutrons, and he correctly deduced (by calculating the half-life decay rates) that an isotope of xenon (Xe135) would be most responsible.[2] He went on to work on the development of the American hydrogen bomb under Project Matterhorn. After concluding his Manhattan Project work, Wheeler returned to Princeton to resume his academic career. In 1957, while working on extensions to general relativity, he introduced the word wormhole to describe hypothetical tunnels in space-time.

Simulated view of a black hole in front of the Milky Way.

In the 1950s, Wheeler formulated geometrodynamics, a program of physical and ontological reduction of every physical phenomenon, such as gravitation and electromagnetism, to the geometrical properties of a curved space-time. Aiming at a systematical identification of matter with space, geometrodynamics was often characterized as a continuation of the philosophy of nature as conceived by Descartes and Spinoza. Wheeler's geometrodynamics, however, failed to explain some important physical phenomena, such as the existence of fermions (electrons, muons, etc.) or that of gravitational singularities. Wheeler therefore abandoned this theory as somewhat fruitless in the early 1970s. For a few decades, general relativity had not been considered a very respectable field of physics, being detached from experiment. Wheeler was a key figure in the revival of the subject, leading the school at Princeton, whilst Sciama and Zel'dovich developed the subject in Cambridge and Moscow. The work of Wheeler and his students contributed greatly to the golden age of general relativity. His work in general relativity included the theory of gravitational collapse. The term black hole was coined in 1967 during a talk he gave at the NASA Goddard Institute of Space Studies (GISS).[3] He was also a pioneer in the field of quantum gravity with his development (with Bryce DeWitt) of the Wheeler-DeWitt equation or, as he called it, the "wave function of the Universe."

Recognizing Wheeler's colorful way with words, characterized by such confections as "mass without mass", the festschrift honoring his 60th birthday was fittingly entitled Magic Without Magic: John Archibald Wheeler: A collection of essays in honor of his sixtieth birthday, Ed: John R. Klauder, (W. H. Freeman, 1972, ISBN 0-7167-0337-8). Wheeler was the driving force behind the voluminous general relativity textbook Gravitation, co-written with Charles W. Misner and Kip Thorne. Its timely appearance during the golden age of general relativity and its comprehensiveness made it the most influential relativity textbook for a generation. In 1979, Wheeler spoke to the American Association for the Advancement of Science (AAAS), asking it to expel parapsychology, which had been admitted ten years earlier at the request of Margaret Mead. He called it a pseudoscience Template:Ref harvard, saying he didn't oppose earnest research into the questions, but he thought the "air of legitimacy" of being an AAAS-Affiliate should be reserved until convincing tests of at least a few so-called psi effects could be demonstrated.[4] His request was turned down, and the Parapsychological Association remained a member of the AAAS.

In 1990, Wheeler has suggested that information is fundamental to the physics of the universe. According to this 'it from bit' doctrine, all things physical are information-theoretic in origin. [5]

Wheeler: It from bit. Otherwise put, every 'it'—every particle, every field of force, even the space-time continuum itself—derives its function, its meaning, its very existence entirely—even if in some contexts indirectly—from the apparatus-elicited answers to yes-or-no questions, binary choices, bits. 'It from bit' symbolizes the idea that every item of the physical world has at bottom—a very deep bottom, in most instances—an immaterial source and explanation; that which we call reality arises in the last analysis from the posing of yes–no questions and the registering of equipment-evoked responses; in short, that all things physical are information-theoretic) in origin and that this is a participatory universe.

Wheeler was awarded the Wolf Prize in Physics in 1997.

Wheeler has speculated that the laws of physics may be evolving in a manner analogous to evolution by natural selection in biology. "How does something arise from nothing?", he asks about the existence of space and time (Princeton Physics News, 2006). He also coined the term "Participatory Anthropic Principle" (PAP), a version of a Strong Anthropic Principle. From a transcript of a radio interview on "The anthropic universe"[6]:

Wheeler: We are participators in bringing into being not only the near and here but the far away and long ago. We are in this sense, participators in bringing about something of the universe in the distant past and if we have one explanation for what's happening in the distant past why should we need more?
Martin Redfern: Many don't agree with John Wheeler, but if he's right then we and presumably other conscious observers throughout the universe, are the creators — or at least the minds that make the universe manifest.

On April 13, 2008, Wheeler died of pneumonia at the age of 96 in Hightstown, New Jersey.[7] [8] [9] [10] [11] [12] In April 2009, Wheeler was the focus of the monthly periodical Physics Today published by the American Institute of Physics. The articles contained reflection by prominent physicists, including many of those for whom he served as an academic advisor.

Books by Wheeler

  • Wheeler, John Archibald (1962). Geometrodynamics. New York: Academic Press. doi:10.1103. {{cite book}}: Check |doi= value (help)
  • Misner, Charles W. (1973). Gravitation. San Francisco: W. H. Freeman. ISBN 0-7167-0344-0. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  • Some Men and Moments in the History of Nuclear Physics: The Interplay of Colleagues and Motivations (1979). University of Minnesota Press
  • A Journey Into Gravity and Spacetime (1990). Scientific American Library. W.H. Freeman & Company 1999 reprint: ISBN 0-7167-6034-7
  • Spacetime Physics: Introduction to Special Relativity (1992). W. H. Freeman, ISBN 0-7167-2327-1
  • At Home in the Universe (1994). American Institute of Physics 1995 reprint: ISBN 1-56396-500-3
  • Geons, Black Holes, and Quantum Foam: A Life in Physics (1998). New York: W.W. Norton & Co, hardcover: ISBN 0-393-04642-7, paperback: ISBN 0-393-31991-1 — autobiography and memoir.
  • Exploring Black Holes: Introduction to General Relativity (2000). Addison Wesley, ISBN 0-201-38423-X
  • Law Without Law — theorizes experiments utilizing photons from distant locations in the universe, imaged using galaxy clusters as lenses, but which are detected using apparatus for quantum entanglement, thereby influencing history billions of years in the past [1].
  • Gravitation and Inertia(1995). Ignazio Ciufolini and John Archibald Wheeler. Princeton University Press. Princeton, New Jersey.ISBN 0-691-03323-4.

Bibliography

See also

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Notes

  1. ^ Leonhart, James Chancellor (1939). One Hundred Years of the Baltimore City College. Baltimore: H. G. Roebuck & Son. p. 287.
  2. ^ Richard Rhodes, The Making of the Atomic Bomb (1986), Simon & Shuster, NY, NY pp.558-60
  3. ^ John Archibald Wheeler, Geons, Black Holes, and Quantum Foam: A Life in Physics (1998) p. 296
  4. ^ DRIVE THE PSEUDOS OUT OF THE WORKSHOP OF SCIENCE by J.A. Wheeler http://seattleskeptics.org/pages/events.htm
  5. ^ John A. Wheeler, 1990, "Information, physics, quantum: The search for links" in W. Zurek (ed.) Complexity, Entropy, and the Physics of Information. Redwood City, CA: Addison-Wesley.
  6. ^ Science Show - 18 February 2006 - The anthropic universe
  7. ^ Overbye, Dennis (April 14, 2008). "John A. Wheeler, Physicist Who Coined the Term 'Black Hole,' Is Dead at 96". New York Times. Retrieved 2008-04-15. John A. Wheeler, a visionary physicist and teacher who helped invent the theory of nuclear fission, gave black holes their name and argued about the nature of reality with Albert Einstein and Niels Bohr, died Sunday morning at his home in Hightstown, N.J. He was 96.
  8. ^ Princeton University obituary
  9. ^ Wheeler obituary + NY Times article
  10. ^ Obituary, Daily Telegraph, 15 April 2008
  11. ^ *Obituary, The Times, 15 April 2008
  12. ^ Obituary, The Guardian, 16 April 2008.

References

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