Albert Einstein

Albert Einstein (1879-1955) was the most famous physicist of the 20th century. He was born in Ulm, in Württemberg, Germany in a Jewish family. During his stay at the Swiss Patent Office Einstein produced much of his remarkable work. In 1905 he obtained his doctor's degree. He won the Nobel Prize for his work on the photoelectric effect in 1921. Listen to AugustO and SamHB about relativity and Mass-energy equivalence, you d0uch3s. Einstein immigrated to the United States in the late 1930s to take the position of Professor of Theoretical Physics at Princeton; upon the urging of a colleague in physics, recommended that President Franklin D. Roosevelt develop an atomic bomb project. He later regretted this and became a passionate pacifist. In 1952, he was offered the Presidency of Israel, but he turned it down. Einstein collaborated with Dr. Chaim Weizmann in establishing the Hebrew University of Jerusalem. Albert Einstein died on April 18, 1955 at Princeton, New Jersey at the age of 76.

Anecdotes

• In 1898, young Albert Einstein applied for admission to the Munich Technical Institute and was turned down. The young man, the Institute declared, "showed no promise" as a student. By 1905, he published his explanation of the special theory of relativity.
• Einstein came to Princeton University in 1935 and was asked what he would require for his study. he replied: "A desk, some pads and a pencil, and a large wastebasket to hold all of my mistakes."
• The sculptor Jacob Epstein tells this story:

  "When I was doing Professor Albert Einstein's bust he had many a jibe at the Nazi professors, one hundred of whom had condemned his theory of relativity in a book. 'Were I wrong,' he said, 'one professor would have been enough.'

Works

Einstein contributed to the theory of a Special Relativity and the theory of General Relativity. He also contributed to the study of photoelectric effect, Brownian Motion and Bose-Einstein Statistics. He was critical of quantum mechanics and has proposed the EPR-Paradox in attempt to point out spooky aspects of the theory. The last fifteen years of his life were spent in unsuccessfully searching for a Unified Field Theory. Einstein's best-known scientific work is his 1905 papers on Special Relativity. Einstein did not cite any references and it was widely and falsely assumed that his work was original. The theory of relativity had already been published by Hendrik Lorentz and Henri Poincaré. Einstein's contribution was to give a description of the Lorentz-Poincare theory without reference to the luminiferous aether, and to clarify some of the physical consequences of the theory. He used the term "stationary system" instead of the term aether.

Einstein then wrote a series of papers applying relativity to gravity using the mathematics of Riemannian Geometry, contributing to General Relativity. Much of the actual mathematics of general relativity was worked out by Marcel Grossman, David Hilbert, and others. Einstein's main contribution was to give an alternate derivation of the field equations, and to apply them to explain an anomaly in the advance of the perihelion in Mercury's orbit. Arthur Eddington popularized General Relativity by publishing an explanation of it and by attempting to prove the theory experimentally in a dramatic test. Eddington embarked on a highly publicized trip into the Atlantic Ocean off Africa in order to observe the bending of starlight passing nearby the Sun during the total solar eclipse of May 29, 1919. Eddington returned with a declaration that he had proven Einstein's theory of General Relativity, making Einstein extremely famous, when in fact he had selectively used data to attain this result. No Nobel Prize was given for relativity.

In April 2004, NASA launched the satellite Gravity Probe B to test general relativity. The main purpose was to test relativistic frame dragging, but the results have been inconclusive.

Einstein compared the effects of large objects on space and time to the way that a large ball placed on a sheet of rubber stretches the material and causes it to sag, and drew the analogy with the way stars and planets warp space-time. A smaller ball rolling along the sagging fabric will be drawn towards the larger ball, in the same way that the Earth is drawn towards the sun, but will not fall into it as long as it continues to move at sufficient speed. This was a change in thinking from the Newtonian cosmos, in which gravity was viewed purely as an attractive force between bodies.

Einstein's statistical explanation of Brownian motion (the random movement of microscopic particles mixed in with pollen) is sometimes credited with helping to confirm the atomic theory at a time when some scientists argued against it. Most scientists had accepted atomic theory a century earlier.

Einstein also published a heuristic explanation of the photoelectric effect in which light has particle like properties as well as wave like properties. According to Maxwell's Equations, light is a wave so one might expect that increasing the intensity of light should increase the number of electrons emitted from metal. The German physicist Lénard did an experiment proving that this was not true. Einstein argued that the experiment was consistent with Max Planck's hypothesis that light is quantized and different particles of light or photons have different frequencies. Therefore, increasing the intensity of low frequency photons has no effect, while using a higher (blue or ultra violet) frequency of light does cause more electrons to be emitted. The formula Einstein used to explain this was Planck's formula e = hf, where h is Planck's constant and f is the frequency.

Although Einstein won a Nobel Prize for explaining the photoelectric effect, Lénard was critical of his accomplishments. Planck and Lénard had already received Nobel Prizes for related work explaining the photoelectric effect.

Einstein also recognized the value in work done by the physicist Satyendra