Hedwig Kohn

Hedwig Kohn (5 April 1887 – 26 November 1964) was a physicist who was one of only three women (along Lise Meitner and Hertha Sponer) to obtain habilitation (the qualification for university teaching) in physics in Germany before World War II. Born in Breslau in the German Empire (now Wrocław, Poland), she was forced to leave Germany during the Nazi regime because she was Jewish. She continued her academic career in the United States, where she settled for the rest of her life.

Biography

Early life Born in Breslau (now Wrocław, Poland), Kohn was the daughter of Georg Kohn, a wholesale merchant of fine cloth, and Helene Hancke, a member of a well-to-do family. Her parents were both German Jews.

In 1907, Kohn enrolled in Breslau University (Universität Breslau, now University of Wrocław), a year before women were officially allowed to matriculate. She became the second woman to enter the physics department. She obtained her doctorate in physics under Otto Lummer in 1913 and was soon appointed as Lummer's assistant. Kohn established a research laboratory for flame spectroscopy while at the college. Kohn also published a textbook that was used to introduce students to radiometry well into the 1960s. Two of her students became professors in Germany.

Honours Kohn is one of the four subjects of Olivia Campbell's 2024 book Sisters in Science.

A Google Doodle on 5 April 2019 commemorated Kohn's 132nd birth anniversary.

Published works

Müller-Pouillets Lehrbuch der Physik. (II. Auflage), unter Mitwirkung zahlreicher Gelehrter herausgegeben von A. Eucken, O. Lummer (+), E. Wätzmann. In five volumes: I. Mechanik und Akustik; II. Lehre von der strahlenden Energie (Optik); III. Wärmelehre; IV. Elektizität und Magnetismus; V. Physik der Erde und des Kosmos (einschl. Relativitätstheorie). Braunschweig: 1925–1929. Band II, Zweite Hälfte, Erster Teil (Volume II, 2nd half, 1st part), volume editor Karl W. Meissner: 1929.