Philosophers Look at Quantum Mechanics pp 33-43 | Cite as

# Bell’s Theorem, Realism, and Locality

## Abstract

Bell’s theorem is sometimes taken to show that quantum mechanics undermines scientific realism. If so, this would be a striking empirical argument against realism. However, Maudlin has claimed that this is a mistake, since Bell’s theorem has precisely one conclusion—namely that quantum mechanics is non-local. I argue here that matters are more complicated than Maudlin acknowledges: quantum mechanics is not a unified theory, and what Bell’s theorem shows of it depends on which interpretation turns out to be tenable. I conclude that while the lesson of Bell’s theorem could be that quantum mechanics is non-local, it could equally be that measurements have multiple outcomes, or that effects can come before their causes, or even, as the anti-realist contends, that no description of the quantum world can be given.

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