William Alfred Fowler (born 9.08.1911) is an American physicist and a member of the National Academy of Sciences (1956). He was born in Pittsburgh. He graduated from Ohio State University and the California Institute of Technology (1936), and has worked at the latter since 1936 (from 1946 as professor, and in 1963-67 as president).
His work was in the fields of nuclear physics, nuclear astrophysics and cosmology. Independently of others he developed (1955) the thermonuclear theory of the formation of the chemical elements in the interiors of stars. In particular, he showed (1957) that the synthesis of heavy elements can proceed by the capture of free neutrons by two paths — in the so-called s- and r-processes. In 1961 he constructed the theory of the s-process. He carried out (1965) a calculation of the cosmological formation of helium, and calculated (1967) the abundance of deuterium and helium-3 at the end of the first three minutes of the expansion of the Universe. He carried out calculations of the flux of solar neutrinos and determined the rate of their capture.
In 1976 he was president of the American Physical Society. T. Bonner Prize (1970), National Medal of Science (1974), A. Eddington Medal (1978).