We have witnessed great advances in quantum information theory in recent years. There are two distinct directions in which progress is currently being made: quantum computation and error correction on the one hand (for a short survey see [1,2]) and non–locality, Bell’s inequalities and purification on the other hand [3,4]. There has also been a number of papers relating the two (e.g. [5,6]). Ou...

It is shown that the model introduced by Cabello et al. to criticize the Franson experiment suffers from the same weakness as the previous model introduced by Aerts et al. with the same purpose. It is also shown why we can assume with confidence that the Franson experiment does violate local realism. In a recent article [1], Cabello et al. introduced a local model which violates a Bell-CHSH ine...

Non-classical probability is the underlying feature of quantum mechanics. The emergence Bell-CHSH non-locality [We stress that CHSH inequality (Clauser et al. in Phys. Rev. Lett. 23(15):880, 1969) more general and reduces to Bell (Bell Physics 1:195, 1964) under assumption perfect correlations between observables] for bipartite systems linear entanglement inequalities two-qubit has been shown A...

We present an experimentally viable approach to demonstrating quantum non-locality in a matter wave system via Rarity-Tapster interferometer using two $s$-wave scattering halos generated by colliding helium Bose-Einstein condensates. The theoretical basis for this method is discussed, and its suitability quantified. As proof of concept, we demonstrate interferometric visibility $V=0.42(9)$, cor...

The derivation of Bell inequalities requires an assumption of measurement independence, related to the amount of free will experimenters have in choosing measurement settings. Violation of these inequalities by singlet state correlations, as has been experimentally observed, brings this assumption into question. A simple measure of the degree of measurement independence is defined for correlati...

It has been recently shown that measurement incompatibility and fine grained uncertainty—a particular form of preparation uncertainty relation—are deeply related to the nonlocal feature of quantum mechanics. In particular, the degree of measurement incompatibility in a no-signaling theory determines the bound on the violation of Bell-CHSH inequality, and a similar role is also played by (fine-g...

Only nite precision measurements are experimentally reasonable, and they cannot distinguish a dense subset from its closure. We show that the rational vectors, which are dense in S 2 , can be colored so that the contradiction with hidden variable theories provided by Kochen-Specker constructions does not obtain. Thus, in contrast to violation of the Bell inequalities, no quantum-over-classical ...

Quantum mechanics and relativistic causality together imply nonlocality: nonlo-cal correlations (that violate the CHSH inequality) and nonlocal equations of motion (the Aharonov-Bohm effect). Can we invert the logical order? We consider a conjecture that nonlocality and relativistic causality together imply quantum mechanics. We show that correlations preserving relativistic causality can viola...