ABSTRACT
According to the relation from Newtonian mechanics, the speeds of a particle in two coordinate systems in relative motion are not necessarily the same. However, the speed of an electromagnetic wave, which may also be regarded as a stream of particles called photons, has been found to always have the same value when measured experimentally in different coordinate systems. Newtonian mechanics is actually erroneous for particles moving at a significant fraction of the speed of light. This chapter presents the relativistically correct equations for the motion of moving particles. General relativity theory includes the effects of gravitation. If there is a gravitational field, then the components of the Riemann curvature tensor are not all zero. Maxwell's equations reduce at the origin of a geodesic coordinate system to the special relativistic form. Transforming the special relativistic form from the geodesic system to an arbitrary coordinate system, the general relativistic form of Maxwell's equations are obtained.
