*** Welcome to piglix ***

Ernst Sigismund Fischer

Ernst S. Fischer
ErnstFischer 1920 MFO9271.jpg
ca. 1920
Born (1875-07-12)12 July 1875
Vienna
Died 14 November 1954(1954-11-14) (aged 79)
Cologne
Nationality Austria
Fields Mathematics
Institutions University of Cologne
Alma mater University of Vienna
Thesis Zur Theorie der Determinanten (1899)
Doctoral advisor Franz Mertens
Leopold Gegenbauer
Doctoral students Hans Falckenberg
Friedrich Neuhaus
Known for Riesz–Fischer theorem
Spouse Ellis Strauss
Children Ursula

Ernst Sigismund Fischer (12 July 1875 – 14 November 1954) was a mathematician born in Vienna, Austria. He worked alongside both Mertens and Minkowski at the Universities of Vienna and Zurich, respectively. He later became professor at the University of Erlangen, where he worked with Emmy Noether.

His main area of research was mathematical analysis, specifically orthonormal sequences of functions which laid groundwork for the emergence of the concept of a Hilbert space.

The Riesz–Fischer theorem in Lebesgue integration is named in his honour.



...
Wikipedia

...