FAQ About Albert Einstein

The theory of relativity consists of two main parts: the special theory of relativity and the general theory of relativity. The special theory, published in 1905, introduced the idea that the laws of physics are the same for all non-accelerating observers and that the speed of light within a vacuum is the same no matter the speed at which an observer travels. The general theory, published in 1915, expanded these ideas to include gravity as a property of space and time, or spacetime, describing how massive objects cause a distortion in spacetime.