Alexander Vilenkin

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Alexander Vilenkin , Russian Александр Виленкин , transcription Alexander Wilenkin, (born May 13, 1949 in Kharkiv , Ukraine ) is a Russian -American theoretical physicist who deals with cosmology .

Alexander Vilenkin 2005 at Harvard

Vilenkin studied physics at Kharkov University , where he also graduated in 1971, but was excluded from further studies for political reasons (he is a Jew, which hindered his academic career and studies in the former Soviet Union, and refused to work with the KGB) . He then did his military service and made ends meet as a laborer, including as a night watchman at the zoo. In 1976 he emigrated to the USA via Italy, where he received his doctorate from the State University of New York in Buffalo in 1977 . As a post-doctoral student, he was at Case Western Reserve University in 1977/78 . From 1978 he was at Tufts University , from 1979 as an assistant professor. There he has been Professor of Physics since 1987 and Director of the Institute of Cosmology since 1989. In 1992 he was a Fairchild Scholar at the California Institute of Technology .

Vilenkin is known for his idea of ​​"Eternal Inflation " (1983) and the quantum mechanical creation of the universe from nothing (1982). This tunnel solution (from a universe with radius 0, ie “nothing”, to one with a finite radius) of the path integral formulation of quantum gravity was an alternative to the “no boundary proposal” developed at the same time by James Hartle and Stephen Hawking . Vilenkin also showed that contrary to Hawking and Hartle's solution, inflation is likely in his solution. In his theory of eternal inflation he argues that in almost all inflationary cosmological solutions new universes are constantly being formed in a kind of chain reaction, an idea that Andrei Linde also adheres to. With his student Arvind Borde, he showed that these models must have had a singularity in the past. In the 2000s, together with Jaume Garriga, he developed the idea of ​​an infinite multitude of parallel universes ( multiverse theory) in which every kind of possible story is realized, infinitely often, "many worlds in one". In contrast to the similarly proceeding many-worlds interpretation of quantum mechanics, they are not superpositions of wave functions. According to Vilenkin, the special position of our universe results from the anthropic principle . Using a variant of this principle (which they called the principle of mediocrity ), Vilenkin predicted a non-zero value for the cosmological constant in 1995 at a time when a vanishing value was generally still favored, before the discovery of the accelerated expansion of the universe. According to his theory, the value of the cosmological constant accepted today has a probability of 0.25.

Vilenkin also made important contributions to the theory of cosmic strings , hypothetical thread-like concentrations of energy in cosmology that may have played a role in structure formation in the early universe.

He was Presidential young investigator of the National Science Foundation (1984) and is a Fellow of the American Physical Society . In 2020 Vilenkin was elected to the National Academy of Sciences .

He has been married since 1973 and has one child.

Fonts

  • (as Alex Vilenkin): Cosmic doppelgangers: How the Big Bang came about - How countless universes arise, Springer Verlag 2008, ISBN 3-540-73917-3 (Many worlds in one - in search for other universes. Hill and Wang 2006, ISBN 0-8090-9523-8 )
  • with Paul Shellard: Cosmic Strings and other topological defects, Cambridge University Press, 1994, 2000

Web links

Individual evidence

  1. ↑ Birth dates according to American Men and Women of Science , Thompson Gale 2005
  2. ↑ Biography at the Templeton Foundation, 2005 ( Memento December 12, 2009 in the Internet Archive ), biography at edge.org
  3. ↑ Vilenkin "The birth of inflationary universes", Physical Review D, Vol. 27, 1983, p. 2848
  4. ↑ Vilenkin, Physics Letters B, Vol. 117, 1982, p. 25
  5. ↑ Vilenkin, Quantum Cosmology and the initial state of the universe, Physical Review, D, Vol. 37, 1988, p. 888
  6. Jump up ↑ Borde, Vilenkin, Eternal inflation and the initial singularity, Physical Review Letters, Vol. 72, 1994, p. 3305
  7. ↑ Vilenkin Physical Review Letters, Vol. 74, 1995, p. 846, Physical Review D, Vol. 52, p. 3365, independent of G. Efstathiou, Monthly Notices Roy, Astron. Soc., L73, 1995, p. 274 , predicted, improved by Steven Weinberg.
personal data
SURNAME Vilenkin, Alexander
ALTERNATIVE NAMES Виленкин, Александр Владимирович (Russian)
BRIEF DESCRIPTION American physicist
DATE OF BIRTH May 13, 1949
PLACE OF BIRTH Kharkiv