Hannes Richter

Edwin E. Salpeter (1924 - 2008)

Hannes Richter

Renowned astrophysicist Edwin E. Salpeter, born in Vienna, died in Ithaca, New York at the age of eighty-three. Long-time professor at Cornell University, where Salpeter was J.G. White Distinguished Professor of Physical Sciences Emeritus, he was a transformative figure in the world of science and his theories revolutionized astrophysics. His exposure to science came at an early age when surrounded by his parents’ (both physicists) friends, who were among the leading academic physicists of Vienna at the time. In 1939, following the Anschluss he emigrated with his parents to Australia at the age of thirteen. Upon winning a scholarship to Birmingham University, he left for England, receiving his PhD in 1948. In 1949 Salpeter attended Cornell as a postdoctoral student, where he spent his remaining career. Salpeter described himself as a “generalist,” with curiosities that spanned a number of fields within physics, including explorations of neuromuscular disorders and the epidemiology of tuberculosis. His most pivotal work, however, included his contribution to the “Salpeter-Bethe equation.” Alongside his mentor and fellow Cornell professor Hans Bethe, in 1967, the two introduced an equation in 1951 showing how helium nuclei fuse to form carbon in the interiors of ancient stars. Until then, the origin of elements beyond helium in the periodic table was unexplained. On the basis of this work, Dr. Salpeter determined the formation rates of stars of different masses. The process remains the basis of today’s studies into the rates of stellar births and deaths. Together with Soviet physicist, Yakov Zledovich, they were the first to propose that a stream of gas falling toward a black hole could in principle be heated to very high temperatures, where it would produce detectable X-rays. Thirty years later, data from the Hubble telescope confirmed his idea. In 1997, Dr. Salpeter and Sir Fred Hoyle, the British scientist who coined the term “Big Bang,” shared the Crafoord Prize from the Royal Swedish Academy of Sciences for “their pioneering contributions involving the study of nuclear reactions in stars and their development.”