Which mathematician was born first, Pyotr Novikov or Dmitri Egorov?
Dmitri Egorov Dmitri Fyodorovich Egorov (Russian: Дми́трий Фёдорович Его́ров ; December 22, 1869 – September 10, 1931) was a Russian and Soviet mathematician known for significant contributions to the areas of differential geometry and mathematical analysis. He was President of the Moscow Mathematical Society (1923 — 1930).
Nikolay Nekhoroshev Nikolai Nikolaevich Nekhoroshev (Russian: Николай Николаевич Нехорошев ; 2 October 1946 – 18 October 2008) was a prominent Soviet Russian mathematician, specializing in classical mechanics and dynamical systems. His research concerned Hamiltonian mechanics, perturbation theory, celestial mechanics, integrable systems, dynamical systems, the quasiclassical approximation, and singularity theory. He proved, in particular, a stability result in KAM-theory stating that, under certain conditions, solutions of nearly integrable systems stay close to invariant tori for exponentially long times .