Special relativity theory constant light speed

Relativity Einstein s theory invoking a constant speed of light, which divides into special relativity and general relativity, the latter describing gravity. 

Let us concentrate on the particle aspect only. The main issue is to identify an space (three- or four-dimensional ) where photons propagate with constant speed c. Einstein s second postulate of the special theory of relativity (STR) requires the speed of light in free space to be the same for all inertial observers. This postulate is conventionally interpreted as implying the non-existence of a preferred frame E. As discussed in section II, the exactly opposite view will be adopted here. 

This is a truly remarkable result. We not only see that the speed of light c is a universal constant that is interrelated to the universal constants po and sg but that this speed is independent of any reference system. You may recall that this was the key assertion in Einstein s theory of special relativity. Here this was predicted from Maxwell s equations some 30 years before. 

Special theory of relativity introduces a fundamental measure of time through signals propagating at a speed independent from the state of uniform motion of sources and sinks. The signal corresponds to electromagnetic radiation (e.g., light). In vacuum, the speed of light is constant. 

There are several effects of relativity on chemical bonding and spectroscopic properties. We first focus on a relativistic effect called the mass-velocity effect. As the electron approaches the speed of light, its mass increases with velocity since in special theory of relativity mass is no longer a constant and varies as... 

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