## The formation of the Institute of Mathematics

(1934 - 1944)

At the formation period, which covered a very difficult decade of the history of the USSR from 1934 to 1944, the directors of the Institute of Mathematics were D. O. Grave (1934 - 1939), M. A. Lavrentyev (1939 - 1941) and G.V. Pfeiffer (1941 - 1944).

At this time, a lot of prominent scholars were working at the institute, including academicians D. O. Grave, M. P.Kravchuk, G. V. Pfeiffer, M. A. Lavrentyev, Corresponding Members N. I. Ahiezer, V. Ye. Dyachenko, M. G. Krein, M. Kh. Orlov, E. Ya. Remez, Yu. D. Sokolov, I. Ya. Steierman.

The institute's scientific growth of potential during 1935 - 1936 facilitated the awarding of academic degrees of Doctor of Physical and Mathematical sciences without thesis defence to N.I.Ahiezer, E.Ya. Remez, Yu. D. Sokolov, I.Ya. Steierman. Even earlier, in 1930, the scientific Doctor degree of Physical and Mathematical sciences was awarded to M. M. Bogolyubov, and in 1938 to M.G. Krein (also without defence of doctoral thesis).

The Institute activities during this period were aimed at research in the field of algebra and number theory, mathematical and functional analysis, the theory of integral and differential equations, probability theory and mathematical statistics, the theory of functions, applied mathematics and mechanics.

D. O. Grave - a brilliant teacher, scholar and organizer of science - during this period (the last period of his life, he died December 19, 1939) worked on the multi-volume monograph "The Treatise on Algebraic Analysis" (he had managed to publish the first two volumes and put into print the third one), had solved a number of practical problems in the distribution of magnetic masses in the Earth, studied the design of airplanes, paid much attention to the mathematical problems of space (supported the ideas of Yuri Kondratyuk, conducted correspondence about the relocation to Kiev of K. E. Tsiolkovsky), prospects for widespread use of computing technology, in particular, based on the use of electric energy. It was he who organized the publication of the Journal of the Institute of Mathematics (in 1934 - 1936, with 4 issues per year).

The Academy of Sciences, including the Institute of Mathematics, met significant losses in the 1930's. During 1936 - 1937, the academic secretary of the institute Corresponding Member M. Kh. Orlov and a research assistant of the Department of Mathematical Statistics prof. V. I. Mozhar were executed by shooting, and also a number of scientists of the Institute were arrested. In 1938 academic M. P. Kravchuk was condemned and exiled to Kolyma, where he died in 1942.

During the period of his creative activity at the Institute of Mathematics (1934 - 1938), M. P. Kravchuk had developed a method of moments for solving linear differential and integral equations and equations of Mathematical Physics.

G. Pfeiffer explored the general problems of integrating equations with partial derivatives, in particular, by generalizing the concept of an integral he created a theory of integrals of these equations that covers Lagrangian integrals and C. Li's integrals.

The Institute carried out an extensive work on the theory of approximation of functions and the approximate solution of differential equations (E. Ya. Remez, M. Kh. Orlov), on celestial mechanics (Yu. D. Sokolov, V. Ye. Dyachenko), on the applied theory elasticity and thin-walled shells (I.J. Steierman). In particular, Yu. D. Sokolov investigated the problem of many bodies, established the conditions for the coincidence of three bodies moving under the influence of Newtonian forces, as well as the conditions of double singing; V. Ya. Dyachenko studied the motion of a material point under the influence of the central non-Newtonian force. M.G. Crane developed the oscillatory theory of linear differential operators, the theory of almost periodic functions on topological groups, the theory of convex sets in a Banach space.

In 1939, with the advent of M. A. Lavrentyev, the Institute of Mathematics began its reorganization: instead of 3 scientific units were created 6 scientific departments: the theory of functions of a complex variable and its applications (head M. A. Lavrentyev), mathematical analysis (G. V. Pfeiffer), mechanics (Yu. D. Sokolov), Applied Mathematics (I. Ya. Steerman), Algebra and Functional Analysis (M. G. Crane), and Lviv Department of Functional Analysis of the Institute of Mathematics (S. Banakh), in which were developed the basics of functional analysis (S. Banakh, S. Mazur, V. Orlych, Yu. Schauder).

During this period, M.A. Lavrentyev obtained significant results in hydrodynamics and in the theory of quasi-conformal mappings, and developed approximate methods for calculating filtration in a heterogeneous medium.

In 1941, the Institute of Mathematics was united with the Institute of Physics and evacuated to Ufa. There were only 29 employees in the joint institute.

In the war period, the institute was focused on the government tasks of provisioning the country's defense capability. Under the direction of M.A. Lavrentyev were conducted researches about the impact of the strike during the explosion of air bombs, the strength of the shells of shells, and was set up and established the manufacture of communication devices for the army and acoustic devices for air defense.

In May 1943, the united institute moved to Moscow, and in the fall of 1944 returned to Kyiv, where the status of the Institute of Mathematics as an independent institution was restored.