The Leggett-Garg inequality (LGI) distinguishes nonmacrorealistic channels from macrorealistic ones by constraining the experimental outcomes of underlying system. In this work, we propose a class which, initially, cannot violate LGI (in form temporal Bell inequality) but can it after application stochastic pre- and post- operations (SPPOs). As proof-of-principle experiment, demonstrate in an a...

Despite claims that Bell’s inequalities are based on the Einstein locality condition, or equivalent, all derivations make an identical mathematical assumption: that local hidden-variable theories produce a set of positive-definite probabilities for detecting a particle with a given spin orientation. The standard argument is that because quantum mechanics assumes that particles are emitted in a ...

We describe a new technique for obtaining Tsirelson bounds, or upper bounds on the quantum value of a Bell inequality. Since quantum correlations do not allow signaling, we obtain a Tsirelson bound by maximizing over all no-signaling probability distributions. This maximization can be cast as a linear program. In a setting where three parties, A, B, and C, share an entangled quantum state of ar...

Despite claims that Bell’s inequalities are based on the Einstein locality condition, or equivalent, all derivations make an identical mathematical assumption: that local hidden-variable theories produce a set of positive-definite probabilities for detecting a particle with a given spin orientation. The standard argument is that because quantum mechanics assumes that particles are emitted in a ...

Despite claims that Bell’s inequalities are based on the Einstein locality condition, or equivalent, all derivations make an identical mathematical assumption: that local hidden-variable theories produce a set of positive-definite probabilities for detecting a particle with a given spin orientation. The standard argument is that because quantum mechanics assumes that particles are emitted in a ...

We give a partial list of 26 tight Bell inequalities for the case where Alice and Bob choose among four two-outcome measurements. All tight Bell inequalities with less settings are reviewed as well. For each inequality we compute numerically the maximal quantum violation, the resistance to noise and the minimal detection efficiency required for closing the detection loophole. Surprisingly, most...

We obtain optimal bounds for the problem of conveying classical messages by communication between a sender and receiver who can utilize non-local correlations obeying the Non-Signaling Principle. These include correlations arising from quantum entanglement, but also include “super-quantum” correlations (e.g. those that maximally violate the CHSH inequality). Our result simultaneously simplifies...

It is shown that Bell’s theorem fails for the Clifford algebra valued local realistic variables. This is made evident by exactly reproducing quantum mechanical expectation value for the EPR-Bohm type spin correlations observable by means of a local, deterministic, Clifford algebra valued variable, without necessitating either remote contextuality or backward causation. Since Clifford product of...

Recently, Agarwal [New J. Phys., 13, 073008(2011)] proposed the generation of a non-Gaussian two-mode quantum vortex state of a system by subtracting a photon from a squeezed vacuum. In the present paper, we study the dynamics of this state under thermal environment. We find strong violation of Bell-CHSH inequality by this state and study the effect of thermal environment on it.