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John Archibald Wheeler

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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, quantum foam and wormhole and the phrase "it from bit".

Biography

John Archibald Wheeler was born in Jacksonville, Florida. He graduated from the Baltimore City College high school in 1926 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.

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. 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.

In the 1950s, he 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.

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

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). 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 (Gardner 1981:185ff), 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. 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.

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":

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.

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. 
• Misner, Charles W.; Kip S. Thorne, John Archibald Wheeler (September 1973). Gravitation. San Francisco: W. H. Freeman. ISBN 0-7167-0344-0. 
• 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

• "Update on John Archibald Wheeler," Princeton Physics News 2 (Winter 2006), Princeton University.

See also

• Holographic principle
• Wheeler's delayed choice experiment
• Genealogy of theoretical physicists
• List of theoretical physicists
• Edwin Power

Wikinews has related news: Physicist John Wheeler dies at age 96

Notes

References

• ^{Gardner 1981} Martin Gardner (1981). Science: Good, Bad, and Bogus. Prometheus Books. ISBN 0-87975-144-4. 

External links

• John Wheeler video at the Peoples Archive
• Princeton University obituary
• Wheeler obituary + NY Times article
• Obituary, Daily Telegraph, 15 April 2008.
• Obituary, The Times, 15 April 2008.
• Obituary, The Guardian, 16 April 2008.
• John Wheeler
• Science Show - 13-09-2003 Profile of John Wheeler
• Law Without Law
• Wheeler's Classic Delayed Choice Experiment
• Annotated bibliography for John Wheeler from the Alsos Digital Library for Nuclear Issues
• Princeton Physics News Volume 2, Issue 1 Winter 2006, (see p. 5)
• Oral History interview transcript with John Archibald Wheeler 5 April 1967, American Institute of Physics, Niels Bohr Library and Archives
• Oral History interview transcript with John Archibald Wheeler 6 December 1993, American Institute of Physics, Niels Bohr Library and Archives
• Cosmic Search Vol. 1 No. 4, FORUM: John A. Wheeler