Albert Einstein 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."
Einstein"s many contributions to physics include his special theory of relativity, which reconciled mechanics with electromagnetism, and his general theory of relativity, a new theory of gravitation which added the principle of equivalence to the principle of relativity. His other contributions include the founding of relativistic cosmology with a cosmological constant, the first post-Newtonian expansions for the perihelion advance of mercury and frame-dragging, the deflection of light by gravity and gravitational lensing, an explanation for capillary action, the first fluctuation dissipation theorem which explaned the Brownian movement of molecules, the photon theory and wave-particle duality from the thermodynamic properties of light, the quantum theory of atomic motion in solids, zero point energy, the semiclassical version of the Schrodinger equation, relations for atomic transition probabilities which predicted stimulated emission, the quantum theory of a monatomic gas which predicted Bose-Einstein condensation, the EPR paradox, and a program for a unified field theory by the geometrization of physics.
Einstein published over 300 scientific works and over 150 non-scientific works. In 1999 Time magazine named him the "Person of the Century", and according to Einstein biographer Don Howard, "to the scientifically literate and the public at large, Einstein is synonymous with genius."