Relativity, Principle of

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Relativity, Principle of

 

one of the fundamental physical laws. According to the principle of relativity, any process will occur identically in an isolated material system that is in a state of rest and in an identical material system that is in a state of uniform linear motion. The state of motion or rest is defined here with respect to an arbitrarily chosen inertial frame of reference; these states are physically completely equivalent. Another way to formulate the principle of relativity is that the laws of physics have the same form in all inertial frames of reference. The principle of relativity and the postulate that the speed of light in a vacuum is independent of the motion of the light source were the basis for Einstein’s special theory of relativity.

I. IU. KOBZAREV

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.