Albert Einstein was a genius, and one of the greatest physicists of all time. His famous Theories of Relativity, which describe the relationship between mass and energy, and between space and time, were published in 1905 and 1916. Einstein was born of Jewish parents in Ulm, Germany. He spent many years in Switzerland, becoming a Swiss citizen in 1901, and gaining his Doctor of Philosophy degree in 1905 from Zurich University. It was while employed as a patent clerk in Berne that he published his first Theory of Relativity. This contained his famous equation: E=mc2, which explains the relationship between mass and energy.