Tomonaga, Sin-Itiro 1906-79
Japanese physicist and Nobel Prize winner

Born in Kyoto, he was educated at Kyoto Imperial University where he was a classmate of Hideki Yukawa. After graduating (1929) Tomonaga joined Yoshio Nishina at Riken, the Institute for Physical and Chemical Research in Tokyo (1932), and during the next five years published papers on positron creation and annihilation, and one on high-energy neutrino-neutron scattering. In 1937 he moved to Leipzig in Germany to work with Werner Heisenberg on a model of the nucleus, returning to Riken in 1939. His most important work was a relativistic quantum description of the interaction between a photon and an electron, producing the theory of 'quantum electrodynamics' for which he shared the 1965 Nobel Prize for physics with Richard Feynman and Julian Schwinger. He was president of the Science Council of Japan (1951) and of Tokyo University (1956).