Theoretical physicist George Placzek was born on September 26, 1905, in Brno, Moravia, an area that is now the Czech Republic. His childhood was spent in Brno and Alexovice, where the Placzek family owned a textile factory. After receiving his PhD from University of Vienna in 1928, Placzek traveled throughout Europe for ten years, working alongside many of the era’s foremost scientific minds, including Enrico Fermi in Rome, Peter Debye and Werner Heisenberg in Leipzig, and Lev Landau in Russia, with whom he derived the Landau-Placzek formula for the ratio of diffusions of light. In 1932, Placzek landed at Niels Bohr’s Copenhagen Institute, where he remained until 1939, when he and many of his colleagues fled Europe for the United States. Placzek was a professor at Cornell University from 1939 to 1942, after which he worked for the General Electric Company until his arrival at the Institute for Advanced Study in 1948. In 1952, Placzek was granted Permanent Member status at the IAS, which he held until his death.

Placzek’s contributions to nuclear theory were substantial: his work with Bohr resulted in the first paper published on the general theory of neutron-based nuclear fission and, later, the discovery of the role of Uranium-235 in creating a nuclear reaction. During the Second World War, Placzek became involved in the Manhattan Project, heading up the Theory Group at Chalk River Laboratories in Montreal and assisting with the final work at Los Alamos. At the IAS, Placzek worked on neutron scattering problems, an understanding of which is crucial to many fields in physics. Placzek died in Zurich on October 9, 1955, at the age of 50.