Einstein first published his theory of special relativity in a German physics journal in 1905. While he was challenging Newton's notions of an absolute space-time (Einstein contended that they were relative) and of unlimited velocity (Einstein proposed that the speed of light was constant and nothing else could reach it), he was ignored by the scientific community.

A true testament to Einstein's genius is the method he used to develop his theory of special relativity; a thought experiment. Einstein considered a light beam moving up and down on a moving train. From the point of view of a person riding on the train, the light would appear to move straight up and straight down. However, from the point of view of someone watching the train, the light would appear to move up, down, and horizontally with the motion of the train. The light would have a diagonal path, and appear to have moved further. However, since Einstein believed that the speed of light was constant, this meant the light's motion must have taken longer (Hawking 80).

This thought experiment was verified many years later. Two highly precise clocks were synchronized, and one clock remained stationary on the earth's surface while the other was flown around the earth. As predicted by special relativity, the clock that had flown around the earth was a fraction of a second behind the clock that had remained stationary, again verifying Einstein's prediction (Hawking 70).

While the predictions of special relativity were astounding, Einstein knew that his theory was imperfect. The primary reason for this was that the theory did not fit with Newton's theory of gravity. While at the German University in Prague 1911, Einstein began to suspect a relationship between acceleration and a gravitational field. Again, Einstein considered the idea of a person inside a box that was accelerating upward. The person would not be able to tell the difference between a force down created by acceleration, or a force down created by a gravitational field. Einstein struggled with this problem until 1912, when he came up with the concept of space-time, which could allow for an equivalence of gravity and acceleration. "His idea was that mass and energy would warp space-time in some manner yet to be determined. Objects like apples or planets would try to move in straight lines through space-time, but their paths would appear to be bent by a gravitational field because space-time is curved" (Hawking 79). Thus general relativity was born and published in 1916.

The first response to general relativity from the scientific community came from Max Planck, while others were either ignoring Einstein's early work on the [special] theory of relativity or passing it by as a mere curiosity" (Bell 547), when he requested clarification from Einstein. It was 14 years, however, until much was heard about this again. On May 29, 1919, British Astronomer Arthur Eddington established an experiment to test general relativity on a small island West of Africa. There was to be a solar eclipse, and if Einstein was right -- that space is curved by gravity -- the light from stars in the Hyades cluster would bend as it approached Earth. Scientists around the world, including Max Planck, stayed up all night to await the results; Einstein slept. The observations confirmed Einstein's predictions precisely, and Einstein said, If Planck had any confidence in relativity he would have gone to bed the way I did" (Discover 52).

Even though the accuracy of general relativity has been proven through experiments many times over, the theory is not still without faults. "On extremely fine scales, space-time, and thus relativity itself, becomes grainy and discontinuous, like a badly overmagnified newspaper photograph. The equations of general relativity simply can't handle such a situation, where the laws of cause and effect break down and particles jump from point A to point B without going through the space in between. In such a world, you can only calculate what will probably happen next--which is just what quantum theory is designed to do" (Nash 83). However, even if his theory breaks down under some circumstances, Einstein can still be considered a great scientist.

Einstein published the theories of specific and general relativity over 80 years ago, and only in the past decade have physicists been able to "catch up" with his predictions and begin the arduous task of verifying them. Also, while general relativity is unable to predict some phenomena, there are other phenomena that it predicts well and quantum theory is unable to handle. In essence, the arena of physics is faced with two half-true theories, and the search for the "grand unified theory" continues to this day. The prominent scientist Richard Feynman is quoted as saying "I still can't see how he thought of it," regarding the theory of general relativity.

The insight and vision that Einstein showed is undeniable proof of his genius. The questions he attempted to answer are some most fundamental that humanity is faced with. It takes a sharp brain to comprehend abstract realms such as space-time. Even more difficult is it to postulate on their existence for the first time as Einstein did.