Georges Lemaître
Mercier recognized the mathematical talent of Georges Lemaître as a young seminarian, and urged him to study Einstein's theories of relativity. Lemaître became an early expert in general relativity as it applied to cosmological questions. He went on to propose an expanding model of the universe, based on both Einstein's and de Sitter's models. Abbé Georges Lemaître developed his Primeval Atom hypothesis, together with researchers of the University of Louvain, and Gamow, Alpher and Herman into the better known Big Bang theory of the origin of the universe.