Abraham Plessner

from Wikipedia, the free encyclopedia

Abraham Ezechiel Plessner (born February 13, 1900 in Łódź , † April 18, 1961 in Moscow ) was a Soviet mathematician who dealt with analysis .

life and work

Plessner was born in Łódź, Russia, as the son of a businessman and factory owner. He attended secondary school (where, in the course of political developments, the language of instruction was alternately Russian, German and, finally, Polish). After graduating from high school in 1918, he studied from 1919 at the University of Gießen (with Ludwig Schlesinger and Friedrich Engel ), the University of Göttingen (with Richard Courant , Edmund Landau , Emmy Noether ) and at the University of Berlin (with Richard von Mises , Ludwig Bieberbach , Issai Shear). In 1923 he received his doctorate from Schlesinger in Gießen ( on the theory of conjugated trigonometric series ). He also assisted Schlesinger in his book on Fourier series and Lebesgue integrals . From 1925 to 1928 he was assistant to Kurt Hensel in Marburg , whom he supported in editing the works of Leopold Kronecker . Then he was again assistant to Schlesinger in Giessen.

Here he completed his habilitation, but despite the efforts of Engel and Schlesinger, he could not become a private lecturer because he was not a German citizen. Plessner went via Berlin to Moscow, where he taught from 1932 at Lomonossow University and at the Steklow Institute for Mathematics of the Soviet Academy of Sciences . In 1935 he completed his habilitation at Moscow University and in 1938 he received a professorship. He was an important member of the Soviet school of functional analysts. In 1949 he lost his posts at the university and the academy due to the influence of Vinogradov . He had health problems that prevented him from improving his small pension by teaching.

Plessner initially dealt with Fourier series and function theory, where Plessner's theorem on the boundary behavior of meromorphic functions in the unit circle disk is named after him. In Moscow he dealt with functional analysis and especially spectral theory (under the influence of the Lusin School, which is dominant in Moscow, and the book Theory des operatorurs lineaire by Stefan Banach ) . His book Spectral Theory of Linear Operators (in Russian), on which he had been working since 1948, was published posthumously in 1965.

Israel Gelfand was one of his students in Moscow .

literature

Web links

References

  1. ↑ Doctoral examination 1922
  2. ↑ Communications of Mathem. Seminar of the University of Giessen, Volume 10, 1923- pp.1-36
  3. ↑ Abraham Plessner On the behavior of analytical functions on the edge of their domain of definition . In: Journal for pure and applied mathematics , Vol. 158 (1927), p. 219, ISSN  0075-4102 Online
personal data
SURNAME Plessner, Abraham
ALTERNATIVE NAMES Plessner, Abraham Ezechiel (full name)
BRIEF DESCRIPTION Soviet mathematician
DATE OF BIRTH February 13, 1900
PLACE OF BIRTH Łódź
DATE OF DEATH April 18, 1961
Place of death Moscow