Albert Einstein

Albert Einstein (March 14, 1879–April 18, 1955) was a theoretical physicist who is widely regarded as the greatest scientist of the 20th century. He proposed the theory of relativity and also made major contributions to the development of quantum mechanics, statistical mechanics and cosmology. He was awarded the 1921 Nobel Prize for Physics for his explanation of the photoelectric effect and "for his services to Theoretical Physics".

After his general theory of relativity was formulated, Einstein became world-famous, an unusual achievement for a scientist. In his later years, his fame exceeded that of any other scientist in history, and in popular culture, Einstein has become synonymous with someone of very high intelligence or the ultimate genius. His face is also one of the most recognizable the world-over. In 1999, Einstein was named "Person of the Century" by Time Magazine. This popularity has also lead to a widespread use of Einstein in advertisement and merchandising, eventually including the registration of Albert Einstein as a trademark.

In his honor, a unit used in photochemistry, the einstein, as well as the chemical element einsteinium and the asteroid 2001 Einstein were named after him.

In November 1915, Einstein presented a series of lectures before the Prussian Academy of Sciences in which he described his theory of general relativity. The final lecture climaxed with his introduction of an equation that replaced Newton's law of gravity. This theory considered all observers to be equivalent, not only those moving at a uniform speed. In general relativity, gravity is no longer a force (as it was in Newton's law of gravity) but is a consequence of the curvature of space-time. The theory provided the foundation for the study of cosmology and gave scientists the tools for understanding many features of the universe that were not discovered until well after Einstein's death. General relativity becomes a method of perceiving all of physics.

The theory was derived with mathematical reasoning and rational analysis, not with experimentation or observation, leading scientists to skepticism. But his equations enabled predictions and tests to be made, and when it was tested by Arthur Eddington by measuring during a solar eclipse how much the light emanating from a star passing close to the sun was bent by the sun's gravity, the predictions from the theory were confirmed. On November 7, 1919, The Times reported the confirmation, and from there on, the theory cemented Einstein's fame, revolutionized physics, and "passed" more tests. (In fact, unlike many other scientific theories, general relativity has held true in every case so far.)