Jacques farming

Jacques Feldbau (born October 22, 1914 in Strasbourg , † April 1945 in Ganacker , Bavaria ) was a French mathematician who dealt with topology .

Life

Jacques Feldbau came from an Orthodox Jewish family of merchants. He graduated from high school in 1932 and began studying at the University of Strasbourg in 1934 . For religious reasons - some of them were on the Sabbath - he was unable to take part in the entrance examinations for the École normal supérieure (ENS), but he was a free listener and received the Agrégation there in 1938 . He then worked with Charles Ehresmann at the University of Strasbourg, where his first publications on topology appeared. In 1939 he was drafted and served in the French Air Force . After the capitulation of France in 1940, it came under the rule of the Nazis. At first he was still active as a high school professor, but was soon dismissed as a Jew. He then followed Ehresmann and Georges Cerf to the French University of Strasbourg, which "exiled" to Clermont-Ferrand . There he worked on his dissertation with Ehresmann, with which he published from 1941 to 1943. Under the Vichy regime he learned the profession of lathe operator and joined the Resistance . He published during this time under the pseudonym Jacques Laboreur. In June 1943 he was arrested in a major raid and deported to Auschwitz in October . There he worked as a clerk in the health department of the rubber factory of IG Farben in Auschwitz-Monowitz . According to fellow inmates, he also organized mathematical seminars. In 1945, two weeks before the end of the war, he took part in the death march of prisoners from Auschwitz, who were removed before the advance of the Soviet army. He died of exhaustion in the Ganacker concentration camp in Bavaria. His sister later had his body transferred.

plant

Feldbau was involved in early research on fiber bundles at Ehresmann's school . In 1939 he proved that a fiber can be trivialized over a simplex. With this he classified fiber bundles over spheres, since as a consequence of his theorem one fiber above the one is given as a mapping from below the automorphism group of the fiber. In his work for his dissertation he developed with Ehresmann what was later called the exact homotopy sequence of fiber spaces and the concept of the associated fiber bundle (the work only appeared under Ehresmann's name, with a note that one of his students was involved). In their work on homotopy groups they were in competition with John Henry Constantine Whitehead , without knowing about it due to the war. Feldbau thus independently found the product of homotopy groups named after Whitehead. ${\displaystyle S^{n}}$ ${\displaystyle S^{n-1}}$

In 1947 a room in the Mathematical Institute of the University of Strasbourg was named after him.

literature

• Michèle Audin Une histoire de Jacques Feldbau , Société mathématique de France, collection T, 2010 (German translation Jacques Feldbau. Topologe , by Springer).

Web links

• Lecture on agriculture by Audin (PDF file, 3.78 MB, French)
• Audin in the Notices AMS 2008 u. a. on agriculture (PDF file, 5.12 MB)

Individual evidence

1. ↑ J. Feldbau: Sur la classification des espaces fibers . In: CR Acad. Sci. Paris . 208, 1939, pp. 1621-1623.
2. ^ J. Feldbau, C. Ehresmann: Sur les propriétés d´homotopie des espaces fibrés . Compte Rendu Academie Science Vol. 212, 1941, p. 945