A. S. Eddington
Sir Arthur Stanley Eddington, OM, FRS was a British astrophysicist of the early 20th century. The Eddington limit, the natural limit to the luminosity of stars, or the radiation generated by accretion onto a compact object, is named in his honour.
He is famous for his work regarding the Theory of Relativity. Eddington wrote a number of articles which announced and explained Einstein's theory of general relativity to the English-speaking world. World War I severed many lines of scientific communication and new developments in German science were not well known in England. He also conducted an expedition to observe the Solar eclipse of May 29, 1919 that provided one of the earliest confirmations of relativity, and he became known for his popular expositions and interpretations of the theory.
“We often think that when we have completed our study of one we know all about two, because 'two' is 'one and one'. We forget that we have still to make a study of 'and'.”