Special Theory of Relativity (Pearson India)

Albert Einstein formulated the special theory of relativity in 1905, in the paper1 ‛On the Electrodynamics of Moving Bodies,’ after considerable contributions by Hendrik Lorentz and Henri Poincaré. It is the physical theory of measurement in inertial frames of reference and generalizes Galileo’s principle of relativity—that all uniform motion is relative and there is no absolute state of rest. Furthermore, the special theory incorporates the principle that the speed of light is the same for all inertial observers, irrespective of the state of motion of the source. The theory is termed special since it applies the principle of relativity only to inertial frames and not to accelerating frames or in gravitational fields. Later, Einstein developed the general theory which is applicable to any frame and it includes the effects of gravity.