A Japanese astrophysicist at Kyoto University who has done important work on the early evolution of stars and of the universe. In 1950 he was the first to offer a variant of the hot Big Bang model as put forward in 1946 by George Gamow and colleagues in the famous "Alpher-Bethe-Gamow" theory. He is best remembered, however, for his discovery of the almost temperature-independent early evolution of pre-main-sequence stars along what has become known as the Hayashi track.
