Relativistic Physics is a generalization of classical mechanics, which was shown to make predictions comparable to those of relativistic physics for velocities and spatial scales encountered in everyday phenomena. Relativistic physics yields quite divergent but experimentally confirmed predictions for velocities approaching that of light, in the realms of large astrophysical distances and of very short, subatomic distances.
Relativistic physics developed from two separate theories put forth by Albert Einstein. The special theory of relativity (1905) was based on a reassessment of the basic notions of space and time and of the way they relate to each other (spacetime). It had deep and surprising consequences, such as the equivalence of mass and energy and the fact that the finite and invariant speed of light in a vacuum is an upper, unreachable limit to the velocities of all material objects. The general theory (c.1916) explained the nature and origins of gravitational fields in terms of changes in the curvature of spacetime induced by the presence of matter and, through later work by other physicists, predicted the existence of previously unforeseen phenomena, such as the existence and properties of black holes.