The Effect of `Probability Skew' in Bell-test Experiments

TL;DR

This paper analyzes how 'probability skew' influences Bell-test experiments, revealing conditions for ruling out local realism and clarifying the role of 'no-signalling' constraints in quantum correlations.

Contribution

It introduces the concept of 'quantum skew' affecting Bell-test outcomes and identifies conditions necessary for conclusively rejecting local realism.

Findings

Results depend on 'quantum skew' of entangled correlations

Certain conditions are necessary to rule out local realism

'No-signalling' constraints cannot be arbitrarily approximated

Abstract

We consider typical experiments that use Bell-inequalities to test local-realist theories of quantum mechanics and gain insight into how certain results can be obtained. We see that results against local-realism arise from some `quantum skew' of the correlation between entangled qubit pairs. Furthermore, we find some conditions necessary for a conclusion against local-realism. Finally we show that the problem of `no-signalling' that arises in these experiments cannot be reduced to arbitrary experimental accuracy.