Quantum effects in relativistic decays

Abstract

By using both explicit time-dependent andS-matrix formalisms of relativistic quantum theory we calculate the decay law of a moving unstable system and show that the classical Einstein time dilation formula is not rigorously applicable in this case and quantum corrections should be taken into account. The consistency of experimental data with Einstein's time dilation formula and the absence of translation-induced decays indicate that the interactions responsible for decays belong to the Dirac instant form dynamics rather than to the point form dynamics. Our results suggest that even though the different forms of dynamics are scattering-equivalent, they are not exactly physically equivalent, as was thought before. Three different experiments with unstable particles are discussed which allow one in principle to determine the details of the interaction governing the decay.