Yuri L. Ershov or Yershov (Юрий Леонидович Ершов, born May 1, 1940 in Novosibirsk) is an outstanding Soviet and Russian mathematician.
Yuri Ershov was born in 1940 in Novosibirsk. In 1958 he entered the Tomsk State University and in 1963 graduated from the Mathematical Department of the Novosibirsk State University. In 1964 he has successfully defended his PhD thesis "Decidable and Undecidable Theories" (advisor Anatolij Mal'tsev). In 1966 he has successfully defended his DrSc thesis "Elementary Theory of Fields".
Apart from being a mathematician, Ershov was a member of the communist party and had different distinguished administrative duties in Novosibirsk State University. Ershov has been accused of antisemitic practices, and his visit to the U.S. in 1980 drew public protests by a number of U.S. mathematicians. Ershov himself denied the validity of these accusations.
Yuri Ershov is a member of the Russian Academy of Sciences and a former Rector of the Novosibirsk State University.
He has been working at the Sobolev Institute of mathematics since 1963. Currently he is Director of this Institute (since 2003). In 1968 he has got a title of Full Professor. In 1970 he was elected to be a Correspondent Member of the Academy of Sciences of the USSR, in 1990 he became Full Member (Academician) of the Russian Academy of Sciences. In 1964-2002 he worked at the Novoasibirsk State University (as second job): in 1968-2002 as a professor, in addition, in 1973-1976 he was Dean of the Mathematical Department of the Novosibirsk State University and Rector of this university in 1985-1993. Yuri L. Ershov is Editor in Chief of the Siberian Mathematical Journal and Editor in Chief of the journal Algebra i Logika (Algebra and Logic).
His basic scientific interests are: algebra, field theory, mathematical logic, algorithm theory, model theory, constructive models, computer science and philosophical aspects of mathematics. He proved decidability of the elementary theory of the field of p-adic numbers (independently proven by J.Ax and S.Kochen), undecidability of the elementary theory of finite symmetric groups, decidability of the elementary theory of relatively complemented distributive lattices.
Yuri Ershov is a Laureate of Malcev's Award of the Russian Academy of Sciences (1992), Russian State Award in the area of Science and Technics (2002,2003), and Lavrentjev's Foundation Award (2007), is decorated with several Russian State Orders.