Lazar Lyusternik

Lazar Aronovich Lyusternik ( _ru. Лазарь Аронович Люстерник), also Lusternik, Lusternick, Ljusternik (born December 31, 1899 in Zduńska Wola, Russian Empire, died July 23, 1981 in Moscow) was a Russian mathematician. He is famous for his work in topology and differential geometry, to which he applied the variational principle. The theory he introduced, togetherwith Lev Schnirelmann, proved a conjecture by Henri Poincaré that every convex body in 3-dimensions has at least three closed geodesics. The ellipsoid with distrinct but nearly equal axis is the critical case with exactly three closed geodesics.

The "Lyusternik-Schnirelmann theory", as it is called now, is based on the previous work by Poincaré, David Birkhoff, and Marston Morse. It has led to numerous advances in differential geometry and topology. For this work Lyusternik received USSR State Prize in 1946.

ee also

* Lyusternik-Schnirelmann category
* Lyusternik's generalization of the Brunn-Minkowski theorem

External links

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[Category:20th century mathematicians