1208.1965 (Adan Cabello)

Quantum nonlocal boxes and nonlocal box swapping    [PDF]

Adan Cabello

Nonlocal boxes (NBs) are theoretical objects that violate a bipartite Bell inequality as much as the no-signaling principle allows. For most bipartite scenarios, NBs are physically impossible to prepare. We show that NBs are physically feasible if the two parties have 3 measurements with 4 outputs. Moreover, we show that, in this case, there is a quantum protocol for NB swapping which allows the parties to locally prepare mixtures of NBs using systems that never interacted. A stronger form of bipartite quantum nonlocality emerges in this scenario: systems that never interacted are as nonlocal as allowed by no-signaling.

View original: http://arxiv.org/abs/1208.1965