Hans Albrecht Bethe (born 2.07.1906) is a theoretical physicist. He was born in Strasbourg. He graduated from the University of Munich (1928). In 1928-33 he taught at the universities of Frankfurt, Stuttgart, Munich and Tübingen, and in 1933-35 at the universities of Manchester and Bristol. In 1935-75 he worked at Cornell University (professor from 1937). In 1943-46 he headed the theoretical division of the Los Alamos laboratory.
His work concerns quantum mechanics, nuclear physics, the problem of nuclear matter, the theory of solids, the theory of nuclear reactors and astrophysics. In 1929 he developed the theory of the crystal field. In 1934 he gave a formula for determining the energy loss of a charged particle as it moves through matter, and in 1951 an equation describing a system of two interacting particles (the Bethe–Salpeter equation). In 1934 he predicted inverse beta decay; independently of others he worked out in 1937 the foundations of the cascade theory of the development of showers in cosmic rays and of the statistical theory of the nucleus. Having carried out an analysis of the thermonuclear processes taking place inside stars, he discovered the cycles of thermonuclear reactions that are the source of the energy of main-sequence stars (Nobel Prize, 1967): the proton-proton cycle (1938, independently of C. Critchfield) and the carbon-nitrogen cycle (1938-39, independently of C. von Weizsäcker).
In 1947, together with R. Marshak, he suggested the existence of two different types of meson. Independently of others he put forward the idea of mass renormalisation (1947) and explained the Lamb shift of the levels, interpreting it as an effect of the interaction of the electron with the radiation field. In 1955 he postulated (independently of R. Sachs) the charge independence of the strong interactions.
A member of a number of academies of sciences and scientific societies. In 1954 he was president of the American Physical Society. The M. Planck (1955) and E. Fermi (1961) medals and others. [48, 558, 559].