Ralph Alpher (b.1921), US physicist. Alpher is best known for his work in cosmological physics. In 1948 he published a paper with Bethe and Gamow in which the abundances of the light elements in the universe could be explained by thermonuclear processes at the very early stages of its evolution. This laid much of the ground work for the hot 'big bang' of the Standard Model of cosmology. Alpher also suggested that the remnants of the big bang would be observable as a background radiation , but red-shifted far into the microwave band. Although the precise temperature of this was wrong, a microwave background was indeed discovered in 1964.