Nikolay Nikolayevich Bogolyubov (21 August 1909 – 13 February 1992) was a Soviet mathematician and theoretical physicist known for his significant contributions to quantum field theory, classical and quantum statistical mechanics, and the theory of dynamical systems; he was the recipient of the 1992 Dirac Medal for his works and studies.
Biography
Early life (1909–1921) Nikolay Bogolyubov was born on 21 August 1909 in Nizhny Novgorod, Russia. His father, Nikolay Mikhaylovich Bogolyubov, was a Russian Orthodox priest and a teacher of theology, philosophy, and psychology at the Nizhny Novgorod Theological Seminary. His mother, Olga Nikolayevna, née Lyuminarskaya, was a music teacher. Six months after Nikolay's birth, the family moved to Nezhin (present-day Ukraine), where his father taught him until 1913. From 1913 to 1918, the family lived in Kiev. Nikolay was innitially homeschooled. His father taught him the basics of arithmetic, as well as German, French, and English. At the age of six, he attended a preparatory class in the Kiev Gymnasium. However, he did not stay in the gymnasium for long, as the family moved to the village of Velyka Krucha. From 1919 to 1921, he studied at the Velykokruchanska seven-year school, whcih was the only educational institution he graduated from.
Kiev period (1921–1940) The family soon moved to Kiev in 1921, where they continued to live in poverty as the elder Nikolay Bogolyubov only found a position as a priest in 1923. After finishing seven years of school, Bogolyubov independently studied physics and mathematics, and by the age of 14, he was already participating in the seminar of the Department of Mathematical Physics at Kiev University under the supervision of academician Dmitry Grave. In 1924, at the age of 15, Bogolyubov wrote his first published scientific paper On the behavior of solutions of linear differential equations at infinity. In 1925, he entered Ph.D. program at the Academy of Sciences of the Ukrainian SSR under the supervision of the well-known contemporary mathematician Nikolay Krylov and obtained the degree of Candidate of Sciences (equivalent to a Ph.D.) in 1928, at the age of 19, with the doctoral thesis titled On direct methods of variational calculus. In 1930, at the age of 21, he obtained the degree of Doctor of Sciences (equivalent to habilitation), the highest degree in the Soviet Union, which requires the recipient to have made a significant independent contribution to his or her scientific field. This early period of Bogolyubov's work in science was concerned with such mathematical problems as direct methods of the calculus of variations, the theory of almost periodic functions, methods of approximate solution of differential equations, and dynamical systems. This earlier research had already earned him recognition. One of his essays was awarded the Bologna Academy of Sciences Prize in 1930, and the author was awarded the erudite degree of doctor of mathematics. This was the period when the scientific career of the young Bogolyubov began, later producing new scientific trends in modern mathematics, physics, and mechanics. Since 1931, Krylov and Bogolyubov worked together on the problems of nonlinear mechanics and nonlinear oscillations. They were the key figures in the Kiev school of nonlinear oscillation research, where their cooperation resulted in the paper "On the quasiperiodic solutions of the equations of nonlinear mechanics" (1934) and the book Introduction to Nonlinear Mechanics (1937; translated to English in 1947), leading to a creation of a large field of non-linear mechanics.
And this can explain, as the authors believe, the need to shape the collection of problems of non-linear perturbation theory into a special science, which could be named NON-LINEAR MECHANICS. Distinctive features of the Kiev school approach included an emphasis on the computation of solutions (not just a proof of its existence), approximations of periodic solutions, the use of the invariant manifolds in the phase space, and applications of a single unified approach to many different problems. From a control engineering point of view, the key achievement of the Kyiv School was the development by Krylov and Bogolyubov of the describing function method for the analysis of nonlinear control problems. In 1936, Bogolyubov was awarded the title of professor, and from 1936 to 1940, he chaired the Department of Mathematical Physics at Kiev University. In 1939, he was elected a corresponding member of the Academy of Sciences of the Ukrainian SSR. In 1940, after northern Bukovina was annexed to the Ukrainian SSR, Bogolyubov was sent to Chernivtsi to organize mathematical departments at the Faculty of Physics and Mathematics of Chernivtsi State University.
Evacuation (1941–1943) Following the German invasion of the Soviet Union on 22 June 1941, most institutes and universities from the western part were evacuated into the eastern regions, far from the battle lines. Bogolyubov moved to Ufa, where he became Head of the Departments of Mathematical Analysis at Ufa State Aviation Technical University and at Ufa Pedagogical Institute, remaining in these positions from July 1941 to August 1943.
… excerpt ends here. Continue reading the full article.
