Louis Witten

Last updated
Louis W. Witten
Born (1921-04-13) April 13, 1921 (age 102)
Nationality American
Alma mater Johns Hopkins University (PhD)
Princeton University
University of Maryland
MIT (postdoctoral research)
Known for Electrovacuum solution
Children Edward Witten
Matt Witten
Celia Witten
Jesse Witten
Scientific career
Fields Gravitation
Institutions Princeton University
Martin Marietta Corporation
University of Cincinnati
University of Florida
Thesis A Model of an Imperfect Gas
Doctoral advisor Theodore H. Berlin

Louis Witten (born April 13, 1921) [1] is an American theoretical physicist and the father of the physicist Edward Witten.

Contents

Witten's research has centered on classical gravitation, including the discovery of certain exact electrovacuum solutions to the Einstein field equation. He edited a book [2] (see citation below) which contains papers by contributors such as ADM (Arnowitt, Deser, and Misner), Choquet-Bruhat, Ehlers and Kundt, Goldberg, and Pirani which are used by researchers after the passage of more than 40 years. His most recent paper was published in 2020. [3]

Early life and education

Louis Witten was born to a Jewish family in Baltimore, Maryland. His parents, Abraham Witten and Bessie Perman, emigrated to the United States from Eastern Europe as teenagers in 1909 and were married in 1916. Witten graduated as a Civil Engineer from Johns Hopkins University in 1941. From 1942 to 1946 he served in the US Army Air Forces as a Radar Weather Officer.[ citation needed ]

He was a graduate student in physics at The Johns Hopkins University from 1948 to 1951 when he received the PhD degree. His dissertation, in statistical mechanics, was entitled "A Model of an Imperfect Gas". His thesis advisor was Theodore H. Berlin. [4] In 1949 he married Lorraine Wollach of Baltimore. They had four children, Edward, Celia, Matthew, and Jesse. Lorraine died in 1987. In 1992 he married Frances Lydia DeLange.

Academic career

After postdoctoral study at Princeton University, the University of Maryland, and the Lincoln Laboratory of MIT, Witten joined RIAS, the research laboratory of the Martin Marietta Corporation. In 1968 he became a Professor of Physics at the University of Cincinnati where he remained until his retirement in 1991. He is also emeritus at the University of Florida. Since 1968 he has been a Vice-President and Director of Science Affairs of the Gravity Research Foundation.

He participated in a conference held at the University of North Carolina at Chapel Hill from January 18–23, 1957 "to discuss the role of gravitation in physics". [note 1]

Bibliography

Notes

Related Research Articles

<span class="mw-page-title-main">General relativity</span> Theory of gravitation as curved spacetime

General relativity, also known as the general theory of relativity and Einstein's theory of gravity, is the geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. General relativity generalises special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time or four-dimensional spacetime. In particular, the curvature of spacetime is directly related to the energy and momentum of whatever matter and radiation are present. The relation is specified by the Einstein field equations, a system of second order partial differential equations.

<span class="mw-page-title-main">Quantum gravity</span> Description of gravity using discrete values

Quantum gravity (QG) is a field of theoretical physics that seeks to describe gravity according to the principles of quantum mechanics. It deals with environments in which neither gravitational nor quantum effects can be ignored, such as in the vicinity of black holes or similar compact astrophysical objects, such as neutron stars as well as in the early stages of the universe moments after the Big Bang.

The following is a timeline of gravitational physics and general relativity.

In theoretical physics, negative mass is a hypothetical type of exotic matter whose mass is of opposite sign to the mass of normal matter, e.g. −1 kg. Such matter would violate one or more energy conditions and show some strange properties such as the oppositely oriented acceleration for an applied force orientation. It is used in certain speculative hypothetical technologies, such as time travel to the past and future, construction of traversable artificial wormholes, which may also allow for time travel, Krasnikov tubes, the Alcubierre drive, and potentially other types of faster-than-light warp drives. Currently, the closest known real representative of such exotic matter is a region of negative pressure density produced by the Casimir effect.

<span class="mw-page-title-main">John Archibald Wheeler</span> American theoretical physicist (1911–2008)

John Archibald Wheeler was an American theoretical physicist. He was largely responsible for reviving interest in general relativity in the United States after World War II. Wheeler also worked with Niels Bohr to explain the basic principles of nuclear fission. Together with Gregory Breit, Wheeler developed the concept of the Breit–Wheeler process. He is best known for popularizing the term "black hole" for objects with gravitational collapse already predicted during the early 20th century, for inventing the terms "quantum foam", "neutron moderator", "wormhole" and "it from bit", and for hypothesizing the "one-electron universe". Stephen Hawking called Wheeler the "hero of the black hole story".

In theoretical physics, geometrodynamics is an attempt to describe spacetime and associated phenomena completely in terms of geometry. Technically, its goal is to unify the fundamental forces and reformulate general relativity as a configuration space of three-metrics, modulo three-dimensional diffeomorphisms. The origin of this idea can be found in an English mathematician William Kingdon Clifford's works. This theory was enthusiastically promoted by John Wheeler in the 1960s, and work on it continues in the 21st century.

A variable speed of light (VSL) is a feature of a family of hypotheses stating that the speed of light may in some way not be constant, for example, that it varies in space or time, or depending on frequency. Accepted classical theories of physics, and in particular general relativity, predict a constant speed of light in any local frame of reference and in some situations these predict apparent variations of the speed of light depending on frame of reference, but this article does not refer to this as a variable speed of light. Various alternative theories of gravitation and cosmology, many of them non-mainstream, incorporate variations in the local speed of light.

Numerical relativity is one of the branches of general relativity that uses numerical methods and algorithms to solve and analyze problems. To this end, supercomputers are often employed to study black holes, gravitational waves, neutron stars and many other phenomena governed by Einstein's theory of general relativity. A currently active field of research in numerical relativity is the simulation of relativistic binaries and their associated gravitational waves.

In general relativity, the sticky bead argument is a simple thought experiment designed to show that gravitational radiation is indeed predicted by general relativity, and can have physical effects. These claims were not widely accepted prior to about 1955, but after the introduction of the bead argument, any remaining doubts soon disappeared from the research literature.

In metric theories of gravitation, particularly general relativity, a static spherically symmetric perfect fluid solution is a spacetime equipped with suitable tensor fields which models a static round ball of a fluid with isotropic pressure.

In theoretical physics, particularly fringe physics, polarizable vacuum (PV) and its associated theory refers to proposals by Harold Puthoff, Robert H. Dicke, and others to develop an analogue of general relativity to describe gravity and its relationship to electromagnetism.

<span class="mw-page-title-main">ADM formalism</span>

The ADM formalism is a Hamiltonian formulation of general relativity that plays an important role in canonical quantum gravity and numerical relativity. It was first published in 1959.

<span class="mw-page-title-main">Canonical quantum gravity</span> A formulation of general relativity

In physics, canonical quantum gravity is an attempt to quantize the canonical formulation of general relativity. It is a Hamiltonian formulation of Einstein's general theory of relativity. The basic theory was outlined by Bryce DeWitt in a seminal 1967 paper, and based on earlier work by Peter G. Bergmann using the so-called canonical quantization techniques for constrained Hamiltonian systems invented by Paul Dirac. Dirac's approach allows the quantization of systems that include gauge symmetries using Hamiltonian techniques in a fixed gauge choice. Newer approaches based in part on the work of DeWitt and Dirac include the Hartle–Hawking state, Regge calculus, the Wheeler–DeWitt equation and loop quantum gravity.

The history of string theory spans several decades of intense research including two superstring revolutions. Through the combined efforts of many researchers, string theory has developed into a broad and varied subject with connections to quantum gravity, particle and condensed matter physics, cosmology, and pure mathematics.

The concept of mass in general relativity (GR) is more subtle to define than the concept of mass in special relativity. In fact, general relativity does not offer a single definition of the term mass, but offers several different definitions that are applicable under different circumstances. Under some circumstances, the mass of a system in general relativity may not even be defined.

Robert Geroch is an American theoretical physicist and professor at the University of Chicago. He has worked prominently on general relativity and mathematical physics and has promoted the use of category theory in mathematics and physics. He was the Ph.D. supervisor for Abhay Ashtekar, Basilis Xanthopoulos and Gary Horowitz. He also proved an important theorem in spin geometry.

<span class="mw-page-title-main">Rainer K. Sachs</span> German-American mathematical physicist

Rainer Kurt "Ray" Sachs is a German-American mathematical physicist, with interests in general relativistic cosmology and astrophysics, as well as a computational radiation biologist. He is professor emeritus of Mathematics and Physics at the University of California, Berkeley, and adjunct professor at Tufts Medical School.

<span class="mw-page-title-main">Arthur Komar</span> American physicist

Arthur Baraway Komar was a theoretical physicist, specializing in general relativity and helping to develop the canonical approach to quantum gravity. Arthur Komar made a significant contribution to physics as an educator, research scientist, and administrator. He had wide interests in numerous other subjects, and his friends knew him as a renaissance man.

Felix Arnold Edward Pirani was a British theoretical physicist, and professor at King's College London, specialising in gravitational physics and general relativity. Pirani and Hermann Bondi wrote a series of articles that established the existence of plane wave solutions for gravitational waves based on general relativity.

References

  1. ORAL HISTORIES: Louis Witten, interviewed by Dean Rickles and Donald Salisbury, at the American Institute of Physics; March 17, 2011; retrieved December 13, 2021
  2. Witten, Louis (1962). Gravitation: An Introduction to Current Research. Wiley.
  3. Herrera, L.; Di Prisco, A.; Ospino, J.; Witten, Louis (2020). "Geodesics of the hyperbolically symmetric black hole". Physical Review D. 101 (6): 064071. arXiv: 2002.07586 . Bibcode:2020PhRvD.101f4071H. doi:10.1103/PhysRevD.101.064071. S2CID   211146232.
  4. Berlin, T. H.; Witten, L.; Gersch, H. A. (1953-10-01). "The Imperfect Gas". Physical Review. 92 (1): 189–201. Bibcode:1953PhRv...92..189B. doi:10.1103/PhysRev.92.189. ISSN   0031-899X.
  5. Cécile M. DeWitt; Dean Rickles (2011). The Role of Gravitation in Physics: Report from the 1957 Chapel Hill Conference. epubli. p. 35. ISBN   978-3-86931-963-6.

Further reading