Allan MacLeod Cormack

Allan MacLeod Cormack (1924-1998) was a South African-born physicist, later an American citizen, born in Johannesburg and educated at the University of Cape Town in physics and crystallography before doctoral studies at St John College, Cambridge. While working as a part-time medical physicist, he developed the mathematical theory showing how X-ray measurements taken from many angles around the body could be combined to reconstruct cross-sectional images, foundational theoretical work for X-ray computed tomography. He later became a professor of physics at Tufts University. For this work, notable in part because he held no doctoral degree in a scientific field, he shared the 1979 Nobel Prize in Physiology or Medicine with Godfrey Hounsfield, who built the first working CT scanners; Cormack also received the National Medal of Science in 1990.