- Lev Pontryagin
Lev Semenovich Pontryagin (Russian: Лев Семёнович Понтрягин) (
3 September 1908 –3 May 1988 ) was a SovietRussia nmathematician . He was born inMoscow and lost his eyesight in a primus stove explosion when he was 14. Despite his blindness he was able to become a mathematician due to the help of his mother Tatyana Andreevna who read mathematical books to him. He made major discoveries in a number of fields of mathematics, including the geometric parts oftopology .Work
He worked on duality theory for homology while still a student. He went on to lay foundations for the abstract theory of the
Fourier transform , now calledPontryagin duality . In topology he posed the basic problem ofcobordism theory . This led to the introduction around 1940 of a theory ofcharacteristic class es, now calledPontryagin class es, designed to vanish on amanifold that is a boundary. Moreover, inoperator theory there are specific instances ofKrein space s calledPontryagin space s.Later in his career he worked in
optimal control theory. His maximum principle is fundamental to the modern theory of optimization. He also introduced there the idea of a bang-bang principle, to describe situations where either the maximum 'steer' should be applied to a system, or none.Pontryagin was a controversial personality. Although he had many Jews among his friends and supported them in his green years, he was accused of anti-Semitism in his mature years. For example he attacked
Nathan Jacobson while both men were vice-presidents of theInternational Mathematical Union O'Connor, John J; Edmund F. Robertson " [http://www-history.mcs.st-andrews.ac.uk/Biographies/Jacobson.html Nathan Jacobson] ". MacTutor History of Mathematics archive. ] . He rejected those charges in an article published in Science in 1979. He also participated in a few notorious political campaigns in the Soviet Union, in particular, in the so-called Luzin affair.ee also
*
Andronov-Pontryagin criterion Notes
External links
*MathGenealogy|id=49073
*MacTutor Biography|id=Pontryagin
* [http://ega-math.narod.ru/LSP/book.htm Autobiography of Pontryagin] (in Russian)
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