On the logical structure of Bell theorems.

Justo Pastor Lambare, Rodney Franco

T. A. Fritz

Colin James

Adán Cabello

A proof of Bell's theorem using two maximally entangled states of two qubits is presented. It exhibits a similar logical structure to Hardy's argument of "nonlocality without inequalities." However, it works for 100% of the runs of a certain experiment. Therefore, it can also be viewed as a Greenberger-Horne-Zeilinger-like proof involving only two spacelike separated regions.

Tomasz Bigaj

Tim Maudlin

Robert Griffiths claims that the consistent histories approach to quantum theory recovers all of the predictions of standard quantum theory and retains the principle of locality, contrary to Bell’s theorem. Griffiths locates the flaw in Bell’s reasoning in his use of standard logic. According to Griffiths, quantum theory requires us to adopt new rules for reasoning, which he calls quantum reasoning. I review the structure of the standard logical connectives and the proof that reasoning by standard logic is always valid. Griffiths’s novel logical “rule,” which is claimed to expose Bell’s error, serves rather only to obscure the fact that the theory Griffiths proposes is inconsistent and hence cannot be correct.