E=mc2 Time and Relativity special theory of relativity 2

Einstein showed, mathematically, that space and time are related and perceived differently by different observers. One consequence of special relativity is time dilation, which means that time in a moving reference frame passes more slowly than time in a stationary reference frame. In other words, a clock that is moving with respect to a stationary observer is perceived by the observer to run more slowly than a stationary clock. Another consequence is length contraction—the observed decrease in length of objects traveling relative to an observer. As part of the special theory of relativity, Einstein also reconceived our understanding of momentum and energy. As the speed of an object approaches the speed of light, its inertia, or resistance to acceleration, also increases. In other words, its mass increases. Additionally, the theory yielded the famous equation E=mc2, which expresses the relationship between energy and mass.