DOES VIOLATION OF BELL-TYPE LOCALITY IMPLY NON-SEPARABILITY IN QUANTUM FIELD THEORY?

Separability was regarded by Einstein as a necessary condition for physics. In particular, he maintained, it is required to hold in field theories. Its violation in quantum theory is due to the existence of entangled states. In this talk I will propose a formulation of separability within the algebraic framework. The latter allows one to apply such a concept to quantum field theory, as well as to contrast the behaviour of relativistic and non-relativistic quantum mechanics. The non-separability of quantum systems located in space-like separated regions of Minkowski space-time can then be shown to be independent from the failure of BellŐs inequalities. I will argue that this reveals quantum correlations that are peculiar of the relativistic case. Specifically, entanglement seems to be of a stronger nature in quantum field theory than in ordinary quantum mechanics.