Thomas Eugene Everhart FREng (born 1932) is an American educator and physicist. He received his A.B. from Harvard University and his M.S. from University of California, Los Angeles. He held a Marshall Scholarship at Clare College Cambridge where he completed a PhD in Physics under Professor Charles Oatley in 1958. He was elected to the National Academy of Engineering in 1978. He served as Chancellor of the University of Illinois at Urbana-Champaign from 1984 to 1987 and as the President of the California Institute of Technology from 1987 to 1997. His area of expertise is the physics of electron beams.
Together with Richard F. M. Thornley he designed the Everhart-Thornley detector. These detectors are still in use in scanning electron microscopes, even though the first such detector was made available as early as 1956.
He was appointed a International Fellow of the Royal Academy of Engineering in 1990.
Everhart currently sits on the board of directors of Raytheon and is a trustee of Caltech.