The German-American physicist Albert Einstein, (1879-1955) contributed more than any other scientist to the 20th-century vision of physical reality. In the wake of World War I, Einstein's theories--especially his theory of relativity--seemed to many people to point to a pure quality of human thought, one far removed from the war and its aftermath. Seldom has a scientist received such public attention for having cultivated the fruit of pure learning.
EARLY LIFE
Einstein's parents, who were nonobservant Jews, moved from Ulm to Munich when Einstein was an infant. The family business was the manufacture of electrical apparatus; when the business failed (1894), the family moved to Milan, Italy. At this time Einstein decided officially to relinquish his German citizenship. Within a year, still without having completed secondary school, Einstein failed an examination that would have allowed him to pursue a course of study leading to a diploma as an electrical engineer at the Swiss Federal Institute of Technology (the Zurich Polytechnic). He spent the next year in nearby Aarau at the cantonal secondary school, where he enjoyed excellent teachers and first-rate facilities in physics. Einstein returned in 1896 to the Zurich Polytechnic, where he graduated (1900) as a secondary school teacher of mathematics and physics.
After a lean two years he obtained a post at the Swiss patent office in Bern. The patent-office work required Einstein's careful attention, but while employed (1902-09) there, he completed an astonishing range of publications in theoretical physics. For the most part these texts were written in his spare time and without the benefit of close contact with either the scientific literature or theoretician colleagues. Einstein submitted one of his scientific papers to the University of Zurich to obtain a Ph.D. degree in 1905. In 1908 he sent a second paper to the University of Bern and became privatdocent, or lecturer, there. The next year Einstein received a regular appointment as associate professor of physics at the University of Zurich.
By 1909, Einstein was recognized throughout German-speaking Europe as a leading scientific thinker. In quick succession he held professorships at the German University of Prague and at the Zurich Polytechnic. In 1914 he advanced to the most prestigious and best-paying post that a theoretical physicist could hold in central Europe: professor at the Kaiser-Wilhelm Gesellschaft in Berlin. Although Einstein held a cross-appointment at the University of Berlin, from this time on he never again taught regular university courses. Einstein remained on the staff at Berlin until 1933, from which time until his death (1955) he held an analogous research position at the Institute for Advanced Study in Princeton, N.J.
SCIENTIFIC WORK
The 1905 Papers
In the first of three seminal papers published in 1905, Einstein examined the phenomenon discovered by Max Planck, according to which electromagnetic energy seemed to be emitted from radiating objects in quantities that were ultimately discrete. The second of Einstein's 1905 papers proposed what is today called the special theory of relativity. The third of Einstein's seminal papers of 1905 concerned statistical mechanics.
The General Theory of Relativity
After 1905, Einstein continued working in all three of the above areas. He made important contributions to the quantum theory, but increasingly he sought to ex
tend the special theory of relativity to phenomena involving acceleration. After a number of false starts, he published (late 1915) the definitive form of the general theory. In its original form, Einstein's general relativity has been verified numerous times in the past 60 years, especially during solar-eclipse expeditions when Einstein's light-deflection prediction could be tested.
LATER LIFE
When British eclipse expeditions in 1919 confirmed his predictions, Einstein was lionized by
the popular press. Einstein's personal ethics also fired public imagination. Einstein, who after returning to Germany in 1914 did not reapply for German citizenship, was one of only a handful of German professors who remained a pacifist and did not support Germany's war aims. After the war, when the victorious allies sought to exclude German scientists from international meetings, Einstein--a Jew traveling with a Swiss passport--remained an acceptable German envoy. Einstein's political views as a pacifist and a Zionist pitted him against conservatives in Germany, who branded him a traitor and a defeatist. The public success accorded his theories of relativity evoked savage attacks in the 1920s by the anti-Semitic physicists Johannes Stark and Philipp Lenard, men who after 1932 tried to create a so-called Aryan physics in Germany. Just how controversial the theories of relativity remained for less flexibly minded physicists is
revealed in the circumstances surrounding Einstein's reception of a Nobel Prize in 1921--it was awarded not for relativity but for his 1905 work on the photoelectric effect.
With the rise of fascism in Germany, Einstein moved (1933) to the United States and abandoned his pacifism. He reluctantly agreed that the new menace had to be put down through force of arms. In this context Einstein sent (1939) a letter to President Franklin D. Roosevelt that urged that the United States proceed to develop an atomic bomb before Germany did. The letter, composed by Einstein's friend Leo Szilard, was one of many exchanged between the White House and Einstein, and it contributed to Roosevelt's decision to fund what became the Manhattan Project.
However much he appeared to the public as a champion of unpopular causes, such as his objection in the 1950s to the House Committee on Un-American Activities and his efforts toward nuclear disarmament, Einstein's central concerns always revolved around physics. At the age of 59, when other theoretical physicists would long since have abandoned original scientific research, Einstein and his co-workers Leopold Infeld and Banesh Hoffmann achieved a major new result in the general theory of relativity.
Until the end of his life Einstein sought a unified field theory, whereby the phenomena of gravitation and electromagnetism could be derived from one set of equations. Few physicists followed Einstein's path in the years after 1920. Quantum mechanics, instead of general relativity, drew their attention. For his part, Einstein could never accept the new quantum mechanics with its principle of indeterminacy, as formulated by Werner Heisenberg and elaborated into a new epistemology by Niels Bohr. Although Einstein's later thoughts were neglected for decades, physicists today refer seriously and awesomely to Einstein's dream--a grand unification of physical theory.
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