In physics, the '''theory of relativity''' is a scientific theory describing the effects due to the invariance of the speed of light. In particular, the meaning of space and time are altered by the motion of the observer. Relativity proposes time dilation and length contraction for observers moving relative to one another at very high ("relativistic") speeds. | In physics, the '''theory of relativity''' is a scientific theory describing the effects due to the invariance of the speed of light. In particular, the meaning of space and time are altered by the motion of the observer. Relativity proposes time dilation and length contraction for observers moving relative to one another at very high ("relativistic") speeds. |