Lawrence C. Biedenharn

Lawrence C. Biedenharn
Lawrence C. Biedenharn

Lawrence Christian Biedenharn, Jr., a prominent mathematical physicist was born on November 18, 1922 in Vicksburg, Mississippi. He attended the Massachusetts Institute of Technology in Cambridge, Massachusetts, served in the Armed Forces as First Lieutenant, US Army Signal Corps from 1942 until 1946, receiving his B.S. degree in absentia in 1944. He was stationed in the Pacific close to the Japanese surrender, and afterwards he was a radio officer for a year in Tokyo. From there he applied to graduate school at MIT, where he obtained his Ph.D. degree in 1950. He was supervised by a famous theorist, Victor Weisskopf, while also working with John Blatt.

Prior to coming to Duke University as a full Professor in 1961, he was a research physicist at the Oak Ridge National Laboratory in Tennessee, Assistant Professor at Yale University and Associate Professor at Rice University. He became James B. Duke Professor in 1987 and Emeritus at the age of seventy in 1992. He then moved to the University of Texas in Austin, where he became Adjunct Professor and continued to teach. He died in Austin of kidney cancer on February 12, 1996.

Biedenharn has made major contributions to the understanding of the role of angular momentum in nuclear reactions and to the theory of excitations in nuclei via the electromagnetic force. Two articles co-authored by Biedenharn with John Blatt and M.E. Rose in the prestigious Review of Modern Physics are among the 100 most cited RMP papers in the period between 1955 and 1985. This came as information from its Editor, David Pines, who in 1986 asked Biedenharn to submit another paper “to try for yet another classic”. His book in 1965 on Coulomb Excitations, co-authored with Pieter Brussaard – who was his postdoctoral associate prior to becoming Professor of Physics at the University of Utrecht in the Netherlands – is an often quoted work. This was the beginning of a very successful series of collaborations with prominent theorists from all over the world who visited Duke and wrote articles and books with him. Such “classic” books were “Angular Momentum in Quantum Physics” and “Racah-Wigner Algebra in Quantum Theory (1981) both with J.D. Louck, which are still authoritative sources on the theory of angular momentum in quantum mechanics. His influential paper on the “Quantum Group Symmetry SU(2)-q” in 1989 was followed by the book on the same subject including “q-Tensor Algebras”, coauthored with Max Lohe, a visiting professor from the University of Adelaide in Australia and appeared only a few months before his death. Biedenharn’s greatest impact has been in the domain of mathematical physics, and he has published many papers emphasizing and developing the concept of symmetry and discreteness by means of which physics can be exploited mathematically. He was a grand master in group theory and quantum mechanics.

He also trained 24 Ph.D. students, and several of them became prominent in turn. He attracted bright postdoctoral associates and had many visiting colleagues with whom he collaborated on articles and books. The productivity and impact of this theoretical group were substantial.

Larry Biedenharn’s many professional activities besides his teaching and research included membership and past chairmanship on a number of National Advisory and Prize committees, and on a National Academy of Science Review committee. In particular he was the chairman and member for a many years of the Eugene Wigner Prize committee on group theory. From 1985 until 1993, he was the editor of the Journal of Mathematical Physics.

He received many honors, among them both Fulbright and Guggenheim awards in 1958, the Alexander von Humboldt Foundation Senior Scientist Award (in 1976 and 1987), the Jesse Beams Medal of the American Physical Society and countless Fellowships and Lecturerships abroad.

Larry and Sarah Biedenharn ca. 1955
Larry and Sarah Biedenharn ca. 1955

Larry met his future wife Sarah Willingham in 1949, when she was a junior at Wellesley College and he was completing his PhD thesis at the MIT. They were married in spring 1950, the year Sarah graduated and began her studies of law at the University of Tennessee, transferring to Yale, when Biedenharn was appointed to the faculty there. She received her LLD from Yale in 1954. They raised two children, John and Sally. Sarah was an invaluable asset to her husband, often accompanying him on his many professional travels and by being a generous host to his graduate students and visitors. Larry told the story that while at MIT he made at that time a desperate – but it turns out successful – effort to lose his strong southern drawl. Nobody in the institutions where he subsequently occupied a position could believe that he hailed from the Deep South.