Gregor Wentzel (17.02.1898-12.08.1978) was a theoretical physicist. He was born in Düsseldorf (now Germany). He graduated from the University of Munich
(1921). In 1926 — 28 he was professor at the University of Leipzig, in 1928-48 at the University of Zurich and in 1948-69 at the University of Chicago.
His work was in the field of the theory of atomic spectra, quantum mechanics, quantum electrodynamics, quantum field theory, scattering theory, the statistical mechanics of many bodies and superconductivity. Independently of L. Brillouin and H. Kramers he developed (1926) a method of finding approximate eigenvalues and eigenfunctions of the one-dimensional Schrödinger equation (the WKB method). He laid the foundations of the general theory of quantised fields (1931). He was the first to apply quantum mechanics to the photoelectric effect and the Auger effect. He developed the strong-coupling theory for the case of a scalar Yukawa field, in which he predicted nucleon isobars (1941). His research also covered meson physics and the meson theory of nuclear forces.
He founded a school of theoretical physicists (V. Bargmann, R. Post, N. Kemmer, V. Telegdi, M. Fierz and others). He was a member of the US National Academy of Sciences (1959). The M. Planck Medal (1976).