Robert Fortet
Robert Fortet (born May 1, 1912 in Boulazac , † July 3, 1998 in Paris ) was a French mathematician who dealt with probability theory and stochastic processes .
Life
Fortet attended a military school (Prytanée militaire de la Fleche) and studied from 1931 at the École normal supérieure (Paris) with the Agrégation in 1934. He received his doctorate in 1939 under Maurice Fréchet at the Sorbonne (Sur l'itération des substitutions algébriques linéaires à une infinitée de variables et ses applications à la théorie des probabilités en chaîne). In his dissertation he dealt with Markov chains with countably infinite states, which he dealt with in Banach spaces . In 1937 he and Wolfgang Doeblin also demonstrated an ergodic theorem in this context (independently proven a little later by Kōsaku Yosida and Shizuo Kakutani ). He was assistant to Georges Darmois in Paris and Chargé de cours at the University of Caen (as a substitute for Ludovic Zoretti ), where he became professor in 1946. In the 1940s he dealt with the diffusion equation and proved a general existence theorem using methods of probabilistic theory (such as the theorem of iterated logarithm and reflection principles). In 1950, 1955 and 1960 he took part in the Berkeley Symposia on Probability Theory. From 1952 he taught at the Sorbonne and in 1960 succeeded Darmois's chair for probability theory and mathematical physics. He also headed a research group at the CNRS as research director for twenty years . After the professorships were closed in 1968, he founded and headed the Laboratoire de probabilités de Jussieu (LPMA) until his retirement in 1980. Since 1951 he was also a professor at the l'École de physique et chimie industrielles de la Ville de Paris.
In 1973 he became a corresponding member of the Académie des sciences .
In 1954 he was invited to speak at the International Congress of Mathematicians in Amsterdam (Convergence de la répartition empirique ver la répartition theorique, pour des élements aléatoires généraux).
His doctoral students include Édith Mourier, André Blanc-Lapierre (1915–2001) and Jacques Neveu .
Fonts
- with Wolfgang Doeblin: Sur des chaînes à liaisons complètes, Bulletin Soc. Math. France, Vol. 65, 1937, pp. 132-148, numdam
- Calcul des probalités: texts mis au point après discussions avec MM. Allard, Destouches, Paris: CNRS 1950
- with A. Blanc-Lapierre: Théorie des fonctions aléatoires: applications à divers phénomènes de fluctuation, Paris: Masson 1953 (Avec un chapitre sur la mécanique des fluides par J. Kampé de Fériet, foreword Georges Darmois)
- English translation: Theory of random functions, Volume 1, Gordon and Breach 1967
- Processus stationnaires et de Markov, entropie, in: La cybernétique, théorie du signal et de l'information, Paris 1951
- Éléments de la théorie des probabilités, 2nd edition, Paris: CNRS 1965
- Elements of probability theory, Gordon and Breach 1971
literature
- Bernard Bru, Jacques Neveau, Obituary in Gazette des Mathematiciens, No. 78, October 1998, online
Web links
Individual evidence
- ↑ Robert Fortet in Mathematics Genealogy Project (English)
| personal data | |
|---|---|
| SURNAME | Go on, Robert |
| BRIEF DESCRIPTION | French mathematician |
| DATE OF BIRTH | May 1, 1912 |
| PLACE OF BIRTH | Boulazac |
| DATE OF DEATH | July 3, 1998 |
| Place of death | Paris |