PR-boxes are sometimes called non-physical, because the allow for model of non-locality beyond quantum mechanics. As it turns out non-signaling strategies allow for a description in the realm of quantum mechanics using honest strategies with two protocols, one with quantum communication from Alice to Bob and another with quantum communication from Bob to Alice. Equipped with this observation and suitable description of quantum games by tensors we can show that there are games with separate classical, quantum and non-signaling strategies with almost optimal parameter control.

This is joint work with Roy Araiza and Carlos Palazuelos (and related to Araiza’s talk).