Albert Einstein

(born March 14, 1879, Ulm, Wrttemberg, Ger.died April 18, 1955, Princeton, N.J., U.S.) German-born Swiss-U.S. scientist. Born to a Jewish family in Germany, he grew up in Munich, and in 1894 he moved to Aarau, Switz. He attended a technical school in Zrich (graduating in 1900) and during this period renounced his German citizenship; stateless for some years, he became a Swiss citizen in 1901. Einstein became a junior examiner (or clerk) at the Swiss patent office in 1902 and began producing original theoretical work that laid many of the foundations for 20th-century physics. He received his doctorate from the University of Zrich in 1905, the same year he won international fame with the publication of four articles: one on Brownian motion, which he explained in terms of molecular kinetic energy; one on the photoelectric effect, in which he demonstrated the particle nature of light; and two on his special theory of relativity, the second of which included his formulation of the equivalence of mass and energy ( = 2). Einstein held several professorships before becoming director of Berlin's Kaiser Wilhelm Institute for Physics in 1913. In 1915 he published his general theory of relativity, which was confirmed experimentally during a solar eclipse in 1919 with observations of the deflection of light passing near the Sun. He received a Nobel Prize in 1921 for his work on the photoelectric effect, his work on relativity still being controversial. For decades he sought to discover the mathematical relationship between electromagnetism and gravitation, which he believed would be a first step toward discovering the common laws governing the behaviour of everything in the universe, but such a unified field theory eluded him. His theories of relativity and gravitation represented a profound advance over Newtonian physics and revolutionized scientific and philosophical inquiry. He resigned his position at the Prussian Academy when Adolf Hitler came to power and moved to Princeton, N.J., where he joined the Institute for Advanced Study. Though a longtime pacifist, he was instrumental in persuading Pres. Franklin Roosevelt in 1939 to initiate the Manhattan Project for the production of an atomic bomb, a technology his own theories greatly furthered, though he did not work on the project himself. Einstein became a U.S. citizen in 1940 but retained his Swiss citizenship. The most eminent scientist in the world in the postwar years, he declined an offer to become the first prime minister of Israel and became a strong advocate for nuclear disarmament.