is the birthday of legendary physicist Albert Einstein, born in Germany in 1879. Einstein took science by storm with his special and general theories of relativity, which dethroned Isaac Newton's laws of mechanics, merged space and time, and established the speed of light as a cosmic limit. The relativity theories, published in 1905 and 1916, ushered in new eras in science and science fiction, inspiring visions of traveling back in time or growing younger by moving at speeds approaching that of light.
Einstein is perhaps best known for his equation E = MC2, which describes the equivalence of mass and energy. He also showed that physical laws should hold true no matter how they are measured, explained the random movement of particles in fluids (called Brownian motion), and laid the foundations for the photon theory of light. Einstein predicted the bending of starlight near the sun or other massive bodies and became a celebrity when this effect was observed during a solar eclipse in 1919. Einstein won the Nobel Prize in physics in 1921 for his work in theoretical physics and particularly for his discovery of the photoelectric effect, in which visible light and other radiation impinging on a substance dislodges electrons from it.
Last fall, Einstein's personal life made news after the auction of love letters to his first wife, Mileva Maric, whom he eventually divorced (see ScienceNOW, 25 November 1996). Einstein died 18 April 1955.