Einstein-Podolsky-Rosen-Bohm experiment with relativistic massive particles

Two aspects of the relativistic version of the EinsteinPodolsky-Rosen-Bohm (EPRB) experiment with massive particles are discussed: (a) a possibility of using the experiment as an implicit test of a relativistic center-of-mass concept, and (b) in uence of the relativistic e ects on degree of violation of the Bell inequality. The nonrelativistic singlet state average h j~a ~ ~b ~ j i = ~a ~b is relativistically generalized by de ning spin via the relativistic center-of-mass operator. The corresponding EPRB average contains relativistic corrections which are stronger in magnitude than standard relativistic phenomena such as the time delay, and can be measured in Einstein-Podolsky-Rosen-Bohm-type experiments with relativistic massive spin-1/2 particles. The degree of violation of the Bell inequality is shown to depend on the velocity of the pair of spin-1/2 particles with respect to laboratory. Experimental con rmation of the relativistic formula would indicate that for relativistic nonzero-spin particles centers of mass and charge do not coincide. The result may have implications for quantum cryptography based on massive particles.