 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.
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.
His work in general relativity included the theory of gravitational collapse; he
coined the term black hole in 1967 during a talk 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 calls 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).
John 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). His move was turned down, and the Parapsychological
Association remained a member of the AAAS.
Wheeler was awarded the Wolf Prize in Physics in 1997.
Wheeler is almost metaphysical in speculating 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 the
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, John Wheeler died of pneumonia at the age of 96 in
Hightstown, New Jersey.
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