Melvin Lax

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Melvin J. Lax (born March 8, 1922 in New York City , † December 8, 2002 in Summit , New York ) was an American theoretical physicist who dealt with solid-state physics, statistical physics, quantum optics and acoustics.

Life

Lax's father had a clothing store in New York. Lax studied at New York University (Bachelor in 1942) and the Massachusetts Institute of Technology , where he made his master's degree in 1943 and received his doctorate in 1947 under Herman Feshbach . At MIT he was assistant to both Feshbach and Philip M. Morse . During his time as a doctoral student, he worked for three years (1942 to 1945) in the underwater acoustics research laboratory of MIT under Feshbach, Morse and RH Bolt on devices for acoustic deception and deflection of torpedoes during World War II . After the end of the war, he completed his doctoral thesis, in which he calculated the cross-section of the generation of mesons by photons and electrons and introduced the approximation later called impulse approximation . After that he went as an assistant professor at the Syracuse University , where he was later a professor. Initially, he dealt with acoustics and nuclear physics , but then switched to semiconductor physics (at the Crystal Branch of the Naval Research Laboratory in 1951). From 1955 he was at Bell Laboratories , where he was head of the theoretical physics department from 1962 to 1964. From 1971 until his death in 2002 he was a professor at the City College of New York , although he remained an advisor to Bell Labs. He was also visiting professor at Princeton University (1961) and Oxford (1961/62).

Since 1983 he has been a member of the National Academy of Sciences , the American Academy of Arts and Sciences and the American Association for the Advancement of Science as well as a Fellow of the American Physical Society . In 1999 he received the Willis E. Lamb Prize .

plant

Lax dealt with multiple scattering of waves (about which he wrote an influential review article in the Reviews of Modern Physics ), acoustics, solid state physics (multi- phonon processes, phonon generation and electron-phonon scattering, Franck-Condon principle in solids, applications of Group theory in solid state physics, spherical model of the interaction of dipoles, disordered solids, the influence of impurities in semiconductors on the transport, impurity bands, non-linear interactions of photons with phonons), theoretical quantum optics , fluctuations in non-equilibrium and noise, for example in lasers ( 1960). This also led to investigations into the separation of signal and noise in laser signals, for example in medicine or after scattering in turbulent media (which at Lax had its roots in secret work during the Second World War to this day). He also dealt with applied mathematics to financial mathematics . Lax was also early involved in approaches to electronic publishing with the American Physical Society. He has published over 200 articles in academic journals and several books. A book on quantum optics was in preparation when he died of cancer.

He received the Lamb Prize for the quantum regression theorem named after him and Lars Onsager from 1963. It is used to calculate the correlation function of fluctuations in driven quantum systems.

Fonts

  • Generalized Mobility Theory , Phys. Rev., Vol. 109, 1958, p. 1921 (Abstract Vol. 100, 1955, p. 1808)
  • The Franck-Condon Principle and its applications to crystals , J. Chem. Phys., Vol. 20, 1952, p. 1752 (the article is a Science Citation Classic)
  • with JC Phillips One dimensional impurity bands , Phys. Rev. Vol. 110, 1958, p. 41
  • with Burstein Infrared absorption in ionic and homopolar crystals , Phys. Rev., Vol. 97, 1955, p. 39
  • Dipoles on a lattice: the spherical model , J. Chem. Phys., Vol. 20, 1952, p. 1351
  • Multiple Scattering of Waves , Rev. Mod. Phys., Vol. 23, 1951, pp. 287-310, Part 2, Phys. Rev., Vol. 85, 1951, p. 621
  • Fluctuations from the non equilibrium steady state , Rev. Mod. Phys., Vol. 32, 1960, p. 25
  • Symmetry principles in solid state and molecular physics , Wiley 1974, Dover 2001
  • with Wei Cai, Min Xu Random processes in physics and finance , Oxford University Press 2006, ISBN 978-0-19-856776-9

literature

  • Joseph L. Birman, Herman Z. Cummins: Melvin Lax 1922-2002 . In: National Academy of Science (Ed.): Biographical Memoirs . tape 87 , 2005 (English, nasonline.org [PDF]).
  • H. Falk (Editor): CCNY Physics Symposium: In celebration of Melvin Lax '60th birthday, City College of New York, 1983

Web links

Individual evidence

  1. ^ Book of Members. Retrieved July 23, 2016 .
  2. ↑ which was examined at the time by, among others, Mark Kac , Berlin and Elliott Montroll
  3. ↑ Lax Formal theory of quantum fluctuations from a driven state , Physical Review, Volume 129, 1963, p. 2342
  4. ↑ Lax Fluctuations and Coherence Phenomena in Classical and Quantum Physics , 1966 Brandeis Summer Institute Lectures (M. Chretien, editor)
  5. ↑ Lax The Lax-Onsager Regression Theorem revisited , Optics Communications, Volume 179, 2000, pp. 463-476
personal data
SURNAME Lax, Melvin
ALTERNATIVE NAMES Lax, Melvin J.
BRIEF DESCRIPTION American theoretical physicist
DATE OF BIRTH March 8, 1922
PLACE OF BIRTH New York City
DATE OF DEATH December 8, 2002
Place of death Summit , New York