Kenneth A. Johnson, a physics professor at MIT for 40 years, died of cancer Tuesday at the MIT Infirmary. Professor Johnson, 67, was a leader in the fields of quantum electrodynamics and quantum field theory.
Professor Johnson, born in Duluth, MN, on March 26, 1931, earned the BS from Illinois Institute of Technology in 1952 and a master's degree and PhD from Harvard University in 1954 and 1955. He was a research fellow and lecturer at Harvard and a National Science Foundation Fellow at the Institute for Theoretical Physics in Copenhagen, Denmark, before joining the MIT faculty in 1958 as an assistant professor. He was promoted to full professor in 1965.
Professor Johnson's research deepened the understanding of quantum field theory and quantum electrodynamics. In quantum field theory, he was the first to observe the dimensional and chiral anomalies. His work in quantum chromodynamics provided a method of describing the properties of a system of confined quarks, the MIT bag model. It was one of the first models to describe the properties of hadrons, including protons and neutrons.
"Ken was an outstanding member of the department in every way," said Profesor Marc Kastner, head of the Department of Physics. "He was a superb mentor for young faculty and students, an excellent classroom teacher and a wise counselor on departmental issues. We all miss him."
"Ken was a widely admired and respected figure in his field," said Professor Francis Low, a colleague and friend for more than 40 years. "He was a marvelous man to have in your department. He sought scientific understanding at the deepest level, but he was alwaysready and able to support and assist his colleagues."
Professor Johnson was a Fellow of the American Physical Society, the American Academy of Arts and Sciences and the American Association for the Advancement of Science.
He is survived by his wife, Gladys (Diaz de los Arcos) of Lincoln; and one son, Keith, a researcher at Alkermes Inc. who lives in Hudson, MA. Burial was private.
A version of this article appeared in MIT Tech Talk on February 24, 1999.