German-American physicist who, in 1905, published three papers, each of which had a profound effect on the development of physics. In one paper, he proposed the theory of special relativity, Eric Weisstein's World of Physics which provides a correct description for particles traveling at high speeds. The two postulates of the special theory of relativity were that the speed of light Eric Weisstein's World of Physics in a vacuum is constant and that the laws of physics are the same for all inertial reference frames. Einstein did know about the Michelson-Morley experiment Eric Weisstein's World of Physics null result, but was not familiar with Lorentz's work after 1895, so he reinvented the Lorentz transformation Eric Weisstein's World of Math for himself (Pais 1982, p. 133).

While special relativity required a modification of the laws of mechanics, the Maxwell equations Eric Weisstein's World of Physics were found to already satisfy the requirements of special relativity. Eric Weisstein's World of Physics Using special relativity, Eric Weisstein's World of Physics Einstein derived the equivalence of rest mass Eric Weisstein's World of Physics m0 and energy Eric Weisstein's World of Physics E, expressible as E2-p2c2 = m02c4, where c is the speed of light Eric Weisstein's World of Physics and p is the (relativistic) momentum Eric Weisstein's World of Physics. When relativistic mass Eric Weisstein's World of Physics is used instead (where ), the equation reduces to the famous E = mc2.

In another 1905 paper, Einstein also explained the photoelectric effect Eric Weisstein's World of Physics by hypothesizing that light consisted of particles (called photons Eric Weisstein's World of Physics) with energy Eric Weisstein's World of Physics equal to , where h is a constant known as Planck's constant Eric Weisstein's World of Physics (named after the physicist Max Planck) and is the frequency Eric Weisstein's World of Physics of the photon. This represented an extension of Planck's quantization to light. The equation Einstein derived was verified experimentally by Millikan in 1916.

Also in 1905, Einstein provided an explanation of Brownian motion Eric Weisstein's World of Physics using kinetic theory, Eric Weisstein's World of Physics stating that it was caused by random collisions of molecules. Einstein furthermore derived an equation stating that a suspension Eric Weisstein's World of Physics of small particles should arrange itself in an exponentially decreasing manner from bottom up. Using Einstein's equations for Brownian motion Eric Weisstein's World of Physics and the distribution of particles, Perrin was able to experimentally measure the value of Boltzmann's constant. Eric Weisstein's World of Physics

Einstein subsequently developed general relativity, Eric Weisstein's World of Physics which postulated that uniform acceleration Eric Weisstein's World of Physics and a gravitational field were equivalent, a statement known as the equivalence principle of gravitation. Eric Weisstein's World of Physics It interpreted gravity Eric Weisstein's World of Physics as a warping of space-time. The general theory of relativity made extensive use of Ricci-Curbastro's tensor calculus. Eric Weisstein's World of Math Einstein investigated cosmological Eric Weisstein's World of Physics modeling, but found that the general theory of relativity would not satisfy the conditions of homogeneity, isotropy, and staticity unless an additional "cosmological constant Eric Weisstein's World of Physics" was added.

Einstein spent the latter portion of his life in an unsuccessful attempt to create a unified theory which would explain all known forces in nature as manifestions of a single fundamental force. Eric Weisstein's World of Physics Einstein's theories were highly controversial for years after he proposed them. In a recommendation for Einstein's membership in the Prussian Academy of Science, the sponsors wrote "In sum, one can say that there is hardly one among the great problems in which modern physics is so rich to which Einstein has not made a remarkable contribution. That he may sometimes have missed the targeting his speculations, as, for example, in his hypothesis of light-quanta, cannot really be held too much against him, for it is not possible to introduce really new ideas even in the most exact sciences without sometimes taking a risk" (Pais 1982, p. 382).

A recent study of Einstein's preserved brain (for details, see Regis 1991) has discovered that the inferior parietal regionthe part thought to be related to mathematical reasoningwas 15% wider than normal (Witelson et al. 1999). In additional, the groove normally running from the front to the back did not extend all the way in Einstein's brain. However, it is unclear what the true significance of these anatomical anomalies are in connection with Einstein's scientific creativity.

Einstein was attacked by some with anti-Jewish leanings. When a pamphlet was published entitled 100 Authors Against Einstein, Einstein retorted "If I were wrong, one would be enough." Some famous Einstein quotes about God include

"Whoever undertakes to set himself up as judge in the field of Truth and Knowledge is shipwrecked by the laughter of the gods."

"I do not believe in immortality of the individual, and I consider ethics to be an exclusively human concern with no superhuman authority behind it."

"I want to know how God created this world. I am not interested in this or that phenomenon, Eric Weisstein's World of Physics in the spectrum of this or that element. I want to know His thoughts, the rest are details."

"God is subtle, but he is not malicious."

"God does not play dice with the world."

"Science without religion is lame, religion without science is blind" (Pais 1982, p. 319).

Einstein also had many insightful things to say about scientific discovery.

"Do not pride yourself on the few great men who, over the centuries, have been born on your earth through no merit of yours. Reflect, rather, on how you treated them at the time and how you have followed their teachings."

"Innovation is not the product of logical thought, even though the final product is tied to a logical structure" (Pais 1982, p. 131).

"Nature shows us only the tail of the lion. But I do not doubt that the lion belongs to it even though he cannot at once reveal himself because of his enormous size" (Pais 1982, p. 235).

"Above stands the marble smile of implacable Nature which has endowed us more with longing than with intellectual capacity" (Pais 1982, p. 343).

"One has been endowed with just enough intelligence to be able to see clearly how utterly inadequate that intelligence is when confronted with what exists. If such humility could be conveyed to everybody, the world of human activities would be more appealing."

"Politics is a pendulum whose swings between anarchy and tyranny are fueled by perennially rejuvenated illusions."

"It is a mistake often made in this country to measure things by the amount of money they cost."

"Do not worry about your difficulties in mathematics; I can assure you that mine are still greater."

"The more success the quantum theory has, the sillier it looks. How nonphysicists would scoff if they were able to follow the odd course of developments!" (Pais 1982, p. 399).

"A practical profession is a salvation for a man of my type; an academic career compels a young man to scientific production, and only strong characters can resist the temptation of superficial analysis."