Born in Khabarovsk, Russia. His father was born in Bessarabia. In 1980 he moved to Novosibirsk, where he received a bachelor's degree from Novosibirsk State University in 1985 and a doctorate from the Novosibirsk Institute of Mathematics in 1988. In 1988 he returned to Khabarovsk, where he worked for 3 years at the Institute of Applied Mathematics. This experience was a difficult one, as the nearest real math library was 2 hours away (one hour by plane, plus one hour by train). He left the Russian Federation in the fall of 1991. During the years 1991-1992 he worked at the Research Institute of Mathematical Sciences and at the University of Maryland. From the summer of 1992 until the summer of 2003, he worked at the University of Utah in Salt Lake City as an associate professor and (since 1997) a professor. In 2003 he moved to the University of California, Davis. In 2007, his department took 4th place in the United States Championship in the academic productivity of the faculty. Author of the books: On the structure of C D spaces with upper curvature bounds, (2019); On the topology and the boundary of N-dimensional RCD (K, N) spaces (2009); Weakly non-collapsed RCD spaces with upper curvature bounds (2019); On Torsion in the Center Conjecture (2018).