Specialist in nuclear physics. 1932 hypothesized the structure of the atomic nucleus as being of protons and neutrons. 1934-1936 with I. Ye.
Tamm developed the principles of the theory of specific nuclear energies. 1944-1948 with I. Ya. Pomeranchuk and A. A. Sokolov developed the theory of electromagnetic radiation emitted by “luminescent” electrons accelerated to high energies in betatron and synchrotron accelerators.
Suggested new linear matrix geometry and proposed theory of parallel transfer of electron spinner wave functions, which permitted generalization of the Dirac quantum equation in the presence of gravity. 1927-1943 at science and education establishements in Leningrad, Kharkov, Tomsk, Sverdlovsk and Kiev.