Valerii Vasil’evich Kozlov

On 1 January 2020 the prominent researcher and academician of the Russian Academy of Sciences Valerii Vasil’evich Kozlov observed his 70th birthday. Kozlov has made fundamental contributions to diverse areas of mathematics and mechanics: the theory of Hamiltonian systems, stability theory, the mechanics of non-holonomic systems, statistical mechanics. He has published about 300 papers on mathematics and mechanics and 8 monographs which are now classical. In this one article it is impossible to give even a brief account of all the directions of his research. Kozlov was born on 1 January 1950 in the village of Kostyli, in the Mikhailovskoe District of the Ryazan Oblast. His mother Ol’ga Arkhipovna was a teacher of mathematics, and his father Vasilii Nestorovich was a train-driver, and a veteran of World War II, from the first days when the Soviet Union was attacked until Victory Day. Valerii started his early school education in his native small village (where nobody lives now). There was only a primary school there, with one female teacher, who gave simultaneous lessons to grades I and III in the morning and to grades II and IV in the afternoon. As an 8-year boy, Kozlov moved with his parents to Lyublino-Dachnaya, close to Moscow. When the Moscow Ring Road was built (in 1961) this settlement, like many others, found itself inside the expanding Moscow. In this way Kozlov became a Moscow resident. During his last two years in secondary school he became deeply interested in mathematics and physics. Three times a week he travelled to lessons at a volunteer physics-mathematics evening school under the auspices of the Bauman Moscow State Technical School (now Technical University). This proved to be a remarkable school! (It was founded in 1962 and still exists.) Most teachers were students