Gustav Hertz brilliantly combined applied research with basic principles

The early 20th century witnessed a revolution in physics, a revolution in which the young Gustav Hertz, born in1887 and nephew of the distinguished physicist Heinrich Hertz, was to play a part. Hertz studied mathematics and physics in Göttingen, Munich and finally Berlin, where he completed his doctorate under Professor Heinrich Ruben in 1911. The young Hertz possessed talents, both as a theorist and an experimenter, and he was given the position of assistant at the physics institute of the Berliner Universität. It was here that he made the acquaintance of James Franck, with whom he conducted the famous Franck-Hertz experiment in 1913. Hertz and Frank were jointly awarded the 1926 Nobel Prize for this experimental electron collision process, which confirmed the fundamental assumption of Niels Bohr’s model for atoms.

Injury, expulsion and recognition

After fighting at the front and being wounded, Hertz completed his Habilitation in 1917 and worked at the Philips labs in Eindhoven (at that time the most modern in the world) from 1920-26, before being appointed professor, first in Halle and then at Technische Hochschule Berlin in 1927, where the new physics institute building had just been completed. Hertz’s work was in the area of isotope separation. His colloquia were also attended by physicists working in industry in Berlin. In addition to understanding the importance of combining applied and basic research, Hertz was also an outstanding teacher. He taught his students how to resist the temptation to disregard difficult intellectual issues as well as the ability to link abstract knowledge and practical applications. In 1934, Hertz, who had now been classified a “half-Jew” by the Nazis, refused to take Hitler’s oath and renounced his tenured professorship. He then set up a research lab at Siemens with four young engineers and between 1939 and 1945 conducted a number of important projects on solid-state technology, ultrasonics, and photoelectric effect.

Scientific work after the war

In 1945 Hertz went to the USSR “at the invitation of the Soviet Union” - in the euphemistic wording of the times. As an expert in the field of isotope separation, Hertz worked on Soviet atomic research as institute director together with other German specialists. A book published in 1992 provided a close examination of these largely unresearched events. In 1954 Hertz returned to Germany to take up work at Leipzig University. In 1957 he supported Heisenberg’s Göttingen Manifesto against plans for atomic weapons. Gustav Hertz died aged 88 on 30 October 1975 in Berlin, highly honored and a member of many academies. He was the only one of the nine distinguished scientists expelled from their positions at Technische Hochschule Berlin to survive the dictatorship and war in the capital of the Third Reich. Today his memory is commemorated in the Gustav Hertz Prize for young physicists.