Kurt Gottfried (May 17, 1929 – August 25, 2022) was an Austrian-born American physicist who was professor emeritus of physics at Cornell University. He was known for his work in the areas of quantum mechanics and particle physics and was also a co-founder with Henry Way Kendall of the Union of Concerned Scientists. He wrote extensively in the areas of physics and arms control. Early life and education Gottfried was born in Vienna, First Austrian Republic, on May 17, 1929. In 1939, after their home in Austria was raided on Kristallnacht, his family emigrated to Montreal, Quebec, Canada. Gottfried attended McGill University, studying both theoretical and engineering physics. Gottfried studied with Victor Weisskopf at the Massachusetts Institute of Technology (MIT) from 1952 to 1955, completing his Ph.D. thesis, Investigations Based on the Bohr-Mottelson Nuclear Model. There he studied deformed nuclei, developing models to describe wave functions and energy levels associated with nucleonic motion in a nonspherical force field, and comparing the results of those models to empirical data. His roommate at MIT was Henry Kendall. Career Gottfried married Sorel Dickstein in 1955, whom he credits as being instrumental in the founding of the Union of Concerned Scientists and an invaluable collaborator over the course of his life. He then held short-term academic positions at Harvard University (1955–1958), CERN, the Niels Bohr Institute, and again at Harvard (1961–1964) before accepting a position in the physics department at Cornell University in 1964. Gottfried became an associate professor at Cornell in 1964, a professor in 1968, and professor emeritus in 1998. He was a visiting professor at MIT from 1968 to 1969, and took a leave of absence to work at CERN from 1970 to 1973. He served as department chair of the Physics department at Cornell University from 1991 to 1994. He died on August 25, 2022, at the age of 93. Research Gottfried worked with J. David Jackson in the 1960s on the production and decay of unstable resonances in high-energy hadronic collisions. They introduced the use of the density matrix to connect production mechanisms to the decay patterns and described the influence of competing processes ("absorption") on the reactions. Gottfried studied meson–nucleon reactions, high-energy electron–proton scattering and the spectroscopy of heavy-quark bound states; and proposed the Gottfried sum rule for deep inelastic scattering to test the elementary quark model. Gottfried's Quantum Mechanics: Fundamentals, originally published in 1966, is considered "one