Alexandru Proca

Alexandru Proca (born October 16, 1897 in Bucharest , † December 13, 1955 in Paris ) was a Romanian-French physicist .

Proca went to study in Paris, where he obtained his physics diploma from Marie Curie and from 1925 worked in her Institut du Radium . He received his doctorate in theoretical physics from Louis de Broglie in 1933 ( on the relativistic theory of Dirac's electron ). The examination committee also included Léon Brillouin and Jean Perrin . In 1929 he became editor of the Annales de l ' Institut Henri Poincaré . In 1934 he was on a Rockefeller scholarship with Erwin Schrödinger at the Friedrich-Wilhelms-Universität zu Berlin and with Niels Bohr at the Institute for Theoretical Physics at the University of Copenhagen , where he also met Werner Heisenberg and George Gamow .

In 1936 he developed the theory of nuclear forces through the exchange of vector mesons (with spin 1). The Proca equation named after him describes a massive spin-1 particle in relativistic quantum mechanics . His theory was used by Hideki Yukawa in his meson theory of nuclear forces, which, however, uses a spin-0 particle ( pion ). Vector mesons only played a role later in the theory of nuclear forces and the electroweak interaction . If one considers z. B. electrodynamics with massive photons (which are vector bosons, i.e. have spin 1), this is described by the Maxwell-Proca equations, which in the limiting case of vanishing photon mass are converted into the Maxwell equations .

His theory of vector mesons brought him international recognition. In 1939 he was invited to the Solvay Conference , which did not take place because of the outbreak of war. During the Second World War he was a senior engineer with French radio for a short time and went to Portugal in 1943, where he lectured in Porto, and was in England from 1943 to 1945. From 1946 he was back in Paris, where he led a well-known seminar that was a center for physicists interested in elementary particle physics in Paris . In his attempt to get a chair at the Sorbonne or at the Collège de France , he was unsuccessful. From 1950 he organized a colloquium in theoretical physics for the CNRS with Pierre Auger and in 1951 he was the French representative at the IUPAP .

From 1953 he suffered from cancer of the throat .

In 1931 he became a French citizen.

In 1990 he was made an honorary member of the Romanian Academy of Sciences.

Web links

• Dorin Poenaru Alexandru Proca (1897–1955), the great physicist , Arxiv 2005

Individual evidence

1. ↑ z. B. Hendrik van Hees, Quantum Field Theory script ( Memento of the original from February 7, 2011 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.