Paul Langevin
Paul Langevin (born January 23, 1872 in Paris , † December 19, 1946 there ) was a French physicist .
Life and professional career
Paul Langevin studied at the École supérieure de physique et de chimie industrielles de la ville de Paris and continued his career there, most recently as director of this university. Since 1909 he held a professorship for physics at the Collège de France . Under German occupation and during the Vichy regime, he lost his professorship at the College de France as a declared opponent of the National Socialists, but received it back in 1944.
Langevin worked on the moderation of neutrons and thus laid a foundation for the construction of nuclear reactors .
The Langevin equation , a stochastic differential equation , is used in statistical physics to describe microscopic processes in the presence of random forces ( noise ), for example Brownian molecular motion in gas molecules. He is the namesake of the Langevin function .
In 1916 he was the first to apply the piezoelectricity of quartz crystals technically with the construction of the first ultrasonic object detection system (sonar) and developed the first echo sounder system for the French Navy . The discovery of the piezo effect goes back to the Curie brothers in 1880 (see piezo effect ).
In 1911, Langevin was elected a corresponding member of the Göttingen Academy of Sciences . Since 1928 he was an external member of the Royal Society . In 1934 he was accepted into the Académie des Sciences .
The Institut Laue-Langevin in Grenoble and the Institut Langevin - Ondes et Images in Paris are also named after Langevin .
Private life
His personal connection with Nobel Prize winner Marie Curie became known to the public as the "Langevin Affair" around 1910.
Langevin was a pacifist. He was at a demonstration by German pacifists under the motto Never again war! Invited to Berlin in 1923, also took part, but refused to speak; the war guilt question still divided the two peoples.
In 1934 he founded, together with the philosopher Émile Chartier (pseudonym Alain), a committee of vigilance (against belligerent endeavors), to which numerous prominent intellectuals from various ideological camps made themselves available.
In 1934, too , he played a key role in the fact that Fritz Karsen, who emigrated from Germany, received approval from the French government to found the École nouvelle de Boulogne in Paris .
His grandson Michel Langevin (1926–1985) married the nuclear physicist Hélène Joliot-Curie , a granddaughter of Marie and Pierre Curie.
Paul Langevin died in Paris on December 19, 1946. His remains have rested in the Panthéon of Paris since 1948.
Individual evidence
- ↑ Holger Krahnke: The members of the Academy of Sciences in Göttingen 1751-2001 (= Treatises of the Academy of Sciences in Göttingen, Philological-Historical Class. Volume 3, Vol. 246 = Treatises of the Academy of Sciences in Göttingen, Mathematical-Physical Class. Episode 3, vol. 50). Vandenhoeck & Ruprecht, Göttingen 2001, ISBN 3-525-82516-1 , p. 144.
- ^ Ilja Ehrenburg : People - Years - Life (Memoirs), Munich 1962, special edition Munich 1965, Volume II 1923–1941, ISBN 3-463-00512-3 , page 328.
Web links
- Literature by and about Paul Langevin in the catalog of the German National Library
- Biography entry at Wolfram Research by Michel Barran (English)
- Entry for Langevin, Paul (1872-1946) in the Archives of the Royal Society , London
personal data | |
---|---|
SURNAME | Langevin, Paul |
BRIEF DESCRIPTION | French physicist |
DATE OF BIRTH | January 23, 1872 |
PLACE OF BIRTH | Paris |
DATE OF DEATH | December 19, 1946 |
Place of death | Paris |