The EPR paradox, Bell's inequality, and the question of locality
Abstract
Most physicists agree that the EinsteinPodolskyRosenBell paradox exemplifies much of the strange behavior of quantum mechanics, but argument persists about what assumptions underlie the paradox. To clarify what the debate is about, we employ a simple and wellknown thought experiment involving two correlated photons to help us focus on the logical assumptions needed to construct the EPR and Bell arguments. The view presented in this paper is that the minimal assumptions behind Bell's inequality are locality and counterfactual definiteness but not scientific realism, determinism, or hidden variables as are often suggested. We further examine the resulting constraints on physical theory with an illustration from the manyworlds interpretation of quantum mechanics—an interpretation that we argue is deterministic, local, and realist but that nonetheless violates the Bell inequality.
 Publication:

American Journal of Physics
 Pub Date:
 January 2010
 DOI:
 10.1119/1.3243279
 arXiv:
 arXiv:0902.3827
 Bibcode:
 2010AmJPh..78..111B
 Keywords:

 Bell theorem;
 EPR paradox;
 physics education;
 quantum optics;
 reviews;
 01.70.+w;
 03.65.w;
 Philosophy of science;
 Quantum mechanics;
 Quantum Physics
 EPrint:
 28 pages