Yuri Trubnikov

Yuri Valentinovich Trubnikov (; 18 March 1946 – 27 April 2025) was a Belarusian mathematician, Doctor of Physical and Mathematical Sciences, and professor, specialising in functional analysis and function theory. He was known for his contributions to nonsmooth analysis, operator equations with accretive nonlinearities, approximation theory, and differential equations. For more than two decades he worked at Vitebsk State University named after P. M. Masherov (VSU), where he founded and headed the scientific school of nonlinear functional analysis. He authored more than 300 scientific, methodological, and review publications, including four monographs.

Biography

Early life and education Yuri Trubnikov was born on 18 March 1946 in Tashkent, Uzbek SSR. Its main results were published in the series of joint papers with Perov, "Monotone differential equations" I–IV, in the journal Differential Equations (1974–1978). After the defence he became a reviewer for Mathematical Reviews and a member of the American Mathematical Society. and from 1998 to 2001 he was an associate professor at the Department of Theoretical and Applied Mathematics of the same university. His publications are indexed in zbMATH Open and Mathematical Reviews, mainly in ordinary differential equations, operator theory, numerical analysis, and complex function theory.

For about fifteen years Trubnikov led research tasks under the State Program of Scientific Research of Belarus. and by Sun Baiyu (China, 2015). Colleagues noted his depth of knowledge and a clear, accessible style of teaching; he described himself as not overly strict but always striving to be objective in assessment. Honorary Certificate of the Ministry of Education of the Republic of Belarus, for many years of fruitful work in the education system and the training of highly qualified specialists (2021). Included in the biographical directory Who Is Who in the Republic of Belarus. Member of the American Mathematical Society; reviewer for Mathematical Reviews for several decades.

Personal life A jubilee profile in the university newspaper My i chas described Trubnikov as "a mathematician with the soul of a lyric poet": he was fond of literature and wrote poetry. His wife was also a mathematician; the couple had a son, Igor, who earned a candidate degree in physical and mathematical sciences and works in information technology, and two daughters, Anastasia and Yulia. He had five grandchildren.

Selected works