Submitted to “Quantum Nonlocality and Reality – 50 Years of Bell’s theorem”
J.S. Bell’s remarkable 1964 theorem showed that any theory sharing the empirical predictions of orthodox quantum mechanics would have to exhibit a surprising — and, from the point of view of relativity theory, very troubling — kind of non-locality. Unfortunately, even still on this 50th anniversary, many commentators and textbook authors continue to misrepresent Bell’s theorem. In particular, one continues to hear the claim that Bell’s result leaves open the option of concluding either non-locality or the failure of some un-orthodox “hidden variable” (or “determinism” or “realism”) premise. This mistaken claim is often based on a failure to appreciate the role of the earlier 1935 argument of Einstein, Podolsky, and Rosen in Bell’s reasoning. After briefly reviewing this situation, I turn to two alternative versions of quantum theory — the “many worlds” theory of Everett and the Quantum Bayesian interpretation of Fuchs, Schack, Caves, and Mermin — which purport to provide actual counterexamples to Bell’s claim that non-locality is required to account for the empirically-verified quantum predictions. After analyzing each theory’s grounds for claiming to explain the EPR-Bell correlations locally, however, one can see that (despite a number of fundamental differences) the two theories share a common for-all-practical-purposes (FAPP) solipsistic character. This dramatically undermines such theories’ claims to provide a local explanation of the correlations and thus, by concretizing the ridiculous philosophical lengths to which one must go to elude Bell’s own conclusion, reinforces the assertion that non-locality really is required to coherently explain the empirical data.