Lev Schnirelmann

{{Infobox scientist

|name = Lev G. Schnirelmann

|image = Л.Г.Шнирельман.jpg

|image_size = 200px

|alt =

|caption = L.G. Schnirelmann in 1925
(from A. O. Gelfond archives)

|birth_date = {{birth date|1905|01|02|df=y}}

|birth_place = Gomel, Russian Empire

|death_date = {{death date and age|1938|09|24|1905|01|02|df=y}}

|death_place = Moscow, RSFSR, Soviet Union

|nationality = Russian

|fields = Mathematics

|workplaces = Steklov Mathematical Institute

|alma_mater = Moscow State University

|doctoral_advisor = Nikolai Luzin

|academic_advisors =

|doctoral_students =

|notable_students =

|known_for = Lusternik–Schnirelmann category
Schnirelmann density
Schnirelmann's constant
Schnirelmann's theorem

|influences =

|influenced =

|awards =

|religion =

|signature =

|signature_alt =

|footnotes =

}}

Lev Genrikhovich Schnirelmann (also Shnirelman, Shnirel'man; {{lang|ru|Лев Ге́нрихович Шнирельма́н}}; 2 January 1905 – 24 September 1938) was a Soviet mathematician who worked on number theory, topology and differential geometry.

Work

Schnirelmann sought to prove Goldbach's conjecture. In 1930, using the Brun sieve, he proved that any natural number greater than 1 can be written as the sum of not more than C prime numbers, where C is an effectively computable constant.Schnirelmann, L.G. (1930). "[http://mi.mathnet.ru/eng/umn/y1939/i6/p9 On the additive properties of numbers]", first published in Proceedings of the Don Polytechnic Institute in Novocherkassk {{in lang|ru}}, vol XIV (1930), pp. 3–27, and reprinted in Uspekhi Matematicheskikh Nauk {{in lang|ru}}, 1939, no. 6, 9–25.Schnirelmann, L.G. (1933). First published as "[https://link.springer.com/article/10.1007/BF01448914 Über additive Eigenschaften von Zahlen]" in Mathematische Annalen (in German), vol 107 (1933), 649-690, and reprinted as "[http://mi.mathnet.ru/eng/umn/y1940/i7/p7 On the additive properties of numbers]" in Uspekhi Matematicheskikh Nauk {{in lang|ru}}, 1940, no. 7, 7–46.

His other fundamental work is joint with Lazar Lyusternik. Together, they developed the Lusternik–Schnirelmann category, as it is called now, based on the previous work by Henri Poincaré, George David Birkhoff, and Marston Morse. The theory gives a global invariant of spaces, and has led to advances in differential geometry and topology. They also proved the theorem of the three geodesics, that a Riemannian manifold topologically equivalent to a sphere has at least three simple closed geodesics.

Biography

Schnirelmann graduated from Moscow State University in 1925 and then worked at the Steklov Mathematical Institute from 1934 to 1938. His advisor was Nikolai Luzin.

Schnirelmann committed suicide in Moscow on 24 September 1938, for reasons that are not clear. According to Lev Pontryagin's memoir from 1998, Schnirelmann gassed himself, due to depression brought on by feelings of inability to work at the same high level as earlier in his career.{{Cite web | url=http://ega-math.narod.ru/LSP/book.htm | title=Л.С.Понтрягин. Жизнеописание}}{{MacTutor Biography|id=Shnirelman}} On the other hand, according to an interview Eugene Dynkin gave in 1988, Schnirelman took his own life after the NKVD tried to recruit him as an informer.{{cite web|url=http://dynkincollection.library.cornell.edu/sites/default/files/Yaglom%20%28ENG%29%2C%20Ithaca%2C%20N.%20Y.%2C%20Dec.%202%2C%201988.pdf|title=The Eugene B. Dynkin Collection of Mathematics Interviews: Akiva M. Yaglom|website=dynkincollection.library.cornell.edu|publisher=Cornell University Library|date=2 December 1988|access-date=11 April 2020}}{{Quote|text=He was an extremely talented mathematician whose premature death in 1938 prevented him from fulfilling his potential... He was a charming young man. The great misfortune of his life was that his lodgings consisted of no more than a wretched furnished room, to which he was ashamed to bring his friends. It was with great embarrassment that he let me see it once. People told me that this alone was what had kept him from marrying.|title=The Apprenticeship of a Mathematician|author=André Weil|source=p. 107-108}}

References

External links

{{MathGenealogy |id=36444}}
[http://kvant.mccme.ru/1996/02/lev_genrihovich_shnirelman.htm Lev Genrihovich Schnirelmann], a popular article by V. Tikhomirov and V. Uspensky {{in lang|ru}}

Category:1905 births

Category:1938 suicides

Category:1938 deaths

Category:People from Gomel

Category:People from Gomelsky Uyezd

Category:Belarusian Jews

Category:Soviet mathematicians

Category:Number theorists

Category:Topologists

Category:Differential geometers

Category:20th-century Belarusian mathematicians

Category:Moscow State University alumni