Born July 22, 1887, in Hamburg. German physicist. Member of the German Academy of Sciences in Berlin. Nephew of Heinrich Hertz.

Gustav Hertz studied at the universities of Göttingen, Munich, and Berlin. In 1917 he became a privatdocent at the University of Berlin. From 1920 to 1925 he worked in the Philips incandescent lamp laboratory in Eindhoven. From 1925 to 1927 he was a professor at the University of Halle and from 1928 to 1935 at the Technische Hochschule in Berlin. Between 1935 and 1945 he was in charge of research in a laboratory of the Siemens company. Hertz worked in the USSR between 1945 and 1954. From 1954 he was a professor and director of the Physics Institute in Leipzig.

In 1913, working together with J. Franck, he carried out the classic studies of the impact of electrons upon gas atoms and molecules (the Franck-Hertz experiment) and experimentally proved the existence of discrete energy levels of an atom. He studied the absorption spectra of X rays. Hertz also pursued research in the areas of electron emission, diffusion and discharge through gases, ultrasonics, semiconductors, and plasma physics. He worked out the diffusion method for separating isotopes. A member of academies of sciences in a number of countries and a foreign member of the Academy of Sciences of the USSR (1958), he received a Nobel Prize in 1925 (with Franck) and the State Prize of the USSR in 1951.