Einstein, Albert (1879-1955), was one of the greatest scientists of all time. He is best known for his theory of relativity, which he first advanced when he was only 26. He also made many other contributions to science. Relativity. Einstein's relativity theory revolutionized scientific thought with new conceptions of time, space, mass, motion, and gravitation. He treated matter and energy as exchangeable, not distinct. In so doing, he laid the basis for controlling the release of energy from the atom. Thus, Einstein was one of the fathers of the nuclear age. Einstein's famous equation, E equals m times c-squared (energy equals mass times the velocity of light squared), became a foundation stone in the development of nuclear energy. Einstein developed his theory through deep philosophical thought and through complex mathematical reasoning. The great scientist was once reported to have said that only a dozen people in the world could understand his theory. However, Einstein always denied this report. See Relativity. Urged atomic research. On Aug. 2, 1939, Einstein wrote a letter to President Franklin D. Roosevelt, explaining that it might be possible to build an atomic bomb. Einstein urged the President to provide governmental help for the study of the release of nuclear energy. Einstein also warned the President that Nazi Germany might already be trying to build an atomic bomb. His letter helped set the United States on the long, difficult, and costly path that finally led to the production of an atomic bomb in 1945. See Nuclear weapon. Early years. Einstein was born on March 14, 1879, in Ulm, Wurttemberg, Germany, the son of Hermann and Pauline Koch Einstein. When Einstein was 5 years old, his father showed him a pocket compass. The little boy was deeply impressed by the mysterious behavior of the compass needle, which kept pointing in the same direction no matter which way the compass was turned. He later said he felt then that "some...
