Born June 26 (July 8), 1895, in Vladivostok; died Apr. 12, 1971, in Moscow. Soviet physicist. Academician of the Academy of Sciences of the USSR (1953; corresponding member, 1933). Hero of Socialist Labor (1953).

After graduating from Moscow University in 1918, Tamm taught at a number of higher educational institutions. He was on the instructional staff of Moscow State University from 1924 to 1941; he returned to the university to teach in 1954. He became affiliated with the Institute of Physics of the Academy of Sciences of the USSR in 1934.

Tamm’s principal works deal with quantum mechanics and its applications, radiation theory, the theory of cosmic rays, and the theory of the interaction of nuclear particles. In 1930 he put forth a quantum theory of the scattering of light in solids and a theory of the scattering of light by electrons. In the field of the quantum theory of metals, Tamm, together with S. P. Shubin, advanced in 1931 a theory of the photoelectric effect in metals. In 1932, Tamm showed theoretically the possibility of the existence of special electron states, now called Tamm levels, on the surfaces of crystals. This achievement provided the foundation for the explanation of various surface effects in crystals. In 1934 he set forth and mathematically developed a quantitative theory of nuclear forces. The modern meson theory of nuclear forces was constructed on the basis of his scheme. In 1937, Tamm and I. M. Frank advanced a theory of the radiation emitted by electrons moving rapidly in a medium (Cherenkov-Vavilov radiation). The Tamm method, which is an approximate method of interpreting the interaction of elementary nuclear particles, was developed by him in 1945. He and Academician A. D. Sakharov proposed in 1950 that a hot plasma in a magnetic field be used to obtain a controlled thermonuclear reaction.

Tamm was the author of the textbook Fundamentals of the Theory of Electricity (1929; 8th ed., 1966). He created a school of theoretical physics, to which many well-known Soviet scientists belong.

Tamm was awarded the Order of Lenin, the Order of the Red Banner of Labor, and several medals. He received the State Prize of the USSR in 1946 and 1953 and a Nobel Prize in 1958.