The Probert Encyclopaedia of Science & Technology

RELATIVITY

Relativity is a theory concerning the nature of space and time propounded by Einstein. The theory consists of two parts. The special theory states that the speed of light is the same for all observers, whatever their speed. That is that light from an object travels at the same velocity whether the object is moving or stationary. The general theory of relativity relates to gravity. Matter in space is said to cause space to curve so as to set up a gravitational field and gravitation becomes a property of space.
Research Relativity