Albert Einstein, (born March 14, 1879, Ulm, Württemberg, Germany—died April 18, 1955, Princeton, New Jersey, U.S.), German-born physicist who developed the special and general theories of relativity and won the Nobel Prize for Physics in 1921 for his explanation of the photoelectric effect. Einstein is generally considered the most influential physicist of the 20th century.
Einstein’s parents were secular, middle-class Jews. His father, Hermann Einstein, was originally a featherbed salesman and later ran an electrochemical factory with moderate success. His mother, the former Pauline Koch, ran the family household. He had one sister, Maria (who went by the name Maja), born two years after Albert.
Einstein would write that two “wonders” deeply affected his early years. The first was his encounter with a compass at age five. He was mystified that invisible forces could deflect the needle. This would lead to a lifelong fascination with invisible forces. The second wonder came at age 12 when he discovered a book of geometry, which he devoured, calling it his “sacred little geometry book.”
Einstein’s education was disrupted by his father’s repeated failures at business. In 1894, after his company failed to get an important contract to electrify the city of Munich, Hermann Einstein moved to Milan to work with a relative. Einstein was left at a boardinghouse in Munich and expected to finish his education. Alone, miserable, and repelled by the looming prospect of military duty when he turned 16, Einstein ran away six months later and landed on the doorstep of his surprised parents. His parents realized the enormous problems that he faced as a school dropout and draft dodger with no employable skills. His prospects did not look promising.
After graduation in 1900, Einstein faced one of the greatest crises in his life. Because he studied advanced subjects on his own, he often cut classes; this earned him the animosity of some professors, especially Heinrich Weber. Unfortunately, Einstein asked Weber for a letter of recommendation. Einstein was subsequently turned down for every academic position that he applied to.
The turning point came later that year, when the father of his lifelong friend Marcel Grossmann was able to recommend him for a position as a clerk in the Swiss patent office in Bern. About then, Einstein’s father became seriously ill and, just before he died, gave his blessing for his son to marry Maric. For years, Einstein would experience enormous sadness remembering that his father had died thinking him a failure.
At first Einstein’s 1905 papers were ignored by the physics community. This began to change after he received the attention of just one physicist, perhaps the most influential physicist of his generation, Max Planck, the founder of the quantum theory.
Soon, owing to Planck’s laudatory comments and to experiments that gradually confirmed his theories, Einstein was invited to lecture at international meetings, such as the Solvay Conferences, and he rose rapidly in the academic world. He was offered a series of positions at increasingly prestigious institutions, including the University of Zürich, the University of Prague, the Swiss Federal Institute of Technology, and finally the University of Berlin, where he served as director of the Kaiser Wilhelm Institute for Physics from 1913 to 1933 (although the opening of the institute was delayed until 1917). Even as his fame spread, Einstein’s marriage was falling apart. He was constantly on the road, speaking at international conferences, and lost in contemplation of relativity. The couple argued frequently about their children and their meager finances. Convinced that his marriage was doomed, Einstein began an affair with a cousin, Elsa Löwenthal, whom he later married. (Elsa was a first cousin on his mother’s side and a second cousin on his father’s side.) When he finally divorced Mileva in 1919, he agreed to give her the money he might receive if he ever won a Nobel Prize.
Einstein also launched the new science of cosmology. His equations predicted that the universe is dynamic—expanding or contracting. This contradicted the prevailing view that the universe was static, so he reluctantly introduced a “cosmological term” to stabilize his model of the universe. In 1929 astronomer Edwin Hubble found that the universe was indeed expanding, thereby confirming Einstein’s earlier work. In 1930, in a visit to the Mount Wilson Observatory near Los Angeles, Einstein met with Hubble and declared the cosmological constant to be his “greatest blunder.” Recent satellite data, however, have shown that the cosmological constant is probably not zero but actually dominates the matter-energy content of the entire universe. Einstein’s “blunder” apparently determines the ultimate fate of the universe.