Arthur Guy Zajonc (/ˈzeɪ.ənts/ ZAY-ənts; born 11 October 1949, Boston, Massachusetts) is a physicist and the author of several books related to science, mind, and spirit; one of these is based on dialogues about quantum mechanics with the Dalai Lama. Zajonc, professor emeritus at Amherst College as of 2012, has been teaching there since 1978. He has served as the General Secretary of the Anthroposophical Society in America. From January 2012 to June 2015 he was president of the Mind and Life Institute.
Zajonc received a B.S. in engineering physics from the University of Michigan in 1971. He received an M.S. (1973) and Ph.D. (1976) in physics at the University of Michigan as well. From 1976-1978 he was a research associate at the Joint Institute for Laboratory Astrophysics at the University of Colorado and the National Bureau of Standards, Boulder, Colorado.
Zajonc became an assistant professor of physics at Amherst College in 1978, and was promoted to associate professor in 1984 and full professor in 1991. In 2006 he became an Andrew W. Mellon Professor at Amherst. He retired from this position in 2011, and is now Andrew W. Mellon Professor Emeritus at Amherst College.
From 1981-82 he was a Visiting Associate Professor of Physics at the École Normale Supérieure at the Laboratoire de Spectroscopie Hertzienne in Paris. In 1984 was a Visiting Research Physicist at the Max Planck Institute for Quantum Optics, Garching (Munich), Germany with H. Walther. In 1986 he was a visiting scientist at the Institute for Quantum Optics at the University of Hanover in Germany. In 1991 he was a visiting scientist at the Department of Physics at the University of Rochester with L. Mandel. In 1993 he was a Fulbright Professor at the University of Innsbruck, Austria teaching and doing research on the experimental foundations of quantum physics.