Fritz Rohrlich
Fritz Rohrlich, a pioneer in quantum electrodynamics, a master of the classical theory of charged particles, and a reflective science educator and philosopher, passed away in DeWitt, New York on 14 November 2018.
Born on 12 May 1921 in Vienna, Rohrlich’s education in Austria was terminated by the arrival of the German army in 1938. He was of Jewish heritage; his parents, Egon and Illy Rohrlich, became Holocaust victims. In 1939 Rohrlich emigrated to Haifa, in modern-day Israel, where in 1943 he earned a Diplom in industrial chemistry from the Technion. Work on a problem on atomic spectra with Giulio Racah (Hebrew University of Jerusalem) was interrupted in 1946 when Rohrlich was accepted for graduate work at Harvard University. He received his doctorate in 1948 for a thesis supervised by Julian Schwinger and also completed Racah’s spectroscopy project. He then spent a year at the Institute for Advanced Study, followed by two years as Hans Bethe’s research associate at Cornell University.
At the Institute and at Cornell, he made significant progress on quantum electrodynamics at a time when profound mathematical difficulties with infinities were being resolved. Rohrlich’s most influential contribution was possibly his treatment of charged particles without spin, where he successfully applied the new techniques of Richard Feynman, Schwinger, and Shin’ichirō Tomonaga. In 1951 Rohrlich married Beulah Friedman, who had a newly minted doctorate in speech communication. Rohrlich moved as an assistant professor to Princeton University, where he taught one of the first quantum electrodynamics courses using the new techniques. In 1953 he moved as an associate professor to the University of Iowa, where he joined Josef M. Jauch. In 1955 he and Jauch published their seminal text on quantum electrodynamics, Theory of Photons and Electrons. Rohrlich was especially pleased by Wolfgang Pauli’s remark about the book: “The more I read it the more I like it.” Rohrlich published a second edition in 1976, two years after Jauch’s death in Switzerland.
In 1963 Rohrlich moved as a full professor to Syracuse University; Beulah also took up a faculty position there in communication and rhetorical studies. Both Rohrlichs spent the rest of their careers at Syracuse. By the time of the move to Syracuse, Fritz Rohrlich’s research activity had broadened to encompass the classical theory of charged particles. The field had been neglected for decades following the discoveries of quantum mechanics. Rohrlich harvested the mathematical techniques of quantum electrodynamics for a flurry of papers. Characteristically, in 1965 Rohrlich published his treatise, Classical Charged Particles. Max Jammer later characterized this book as a “unique masterpiece.” Rohrlich remained active in this field until the end of his life, publishing second (1990) and third editions (2007) of his book and a paper in Physical Review E in 2008.
In the 1970s and 1980s, Rohrlich became increasingly active in the philosophy of science. With C. L. Hardin, his philosophy colleague at Syracuse, he published the essay “Established Theories” in 1983. Their essay placed physical theories in the context of subsequent revisions. An example is the refinement of classical Newtonian mechanics after two centuries to accommodate special relativity. At Syracuse, Rohrlich taught an unusual, nontechnical course combining elements of the philosophy of science with elementary treatments of relativity and quantum mechanics. Based on this course, in 1987 Rohrlich published his third book, the text From Paradox to Reality: Our Basic Concepts of the Physical World.
Beyond his published contributions, Rohrlich worked behind the scenes to foster the education, careers, and lives of his students and colleagues. His early life did not deprive him of an understated sense of humor. He was a passionate devotee of classical music and an active member of the Syracuse Friends of Chamber Music. Rohrlich retired in 1991, but he continued publishing and reviewing for two more decades. Beulah died in 1993, and in 1994 Fritz Rohrlich married Phyllis Klein Lavelanet, who survives him.
Rohrlich was a fellow and an outstanding referee of the American Physical Society, a Fulbright Lecturer, and the recipient of an honorary doctorate from the University of Graz. In 1994 Jammer published an extended appreciation of Rohrlich’s work.
