Albert Einstein (14 March 1879 – 18 April 1955) was a German-born theoretical physicist. He is best known for his theory of relativity and specifically mass–energy equivalence, expressed by the equation E = mc2. Einstein received the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect."[1] Einstein published over 300 scientific works and over 150 non-scientific works.[2][3] In 1999 Time magazine named him the "Person of the Century". In wider culture the name "Einstein" has become synonymous with genius.