NEW TOOLS TO INVESTIGATE NON-CLASSICAL CORRELATIONS

Abstract

We are primarily interested in correlations being inherent of quantum mechanics and absent in any local realistic model. We would like to present our developments on techniques to study contextuality and entropic Bell inequalities. In more detail, we propose a new approach to investigate a state-independent contextuality. It uses only one copy of system, does not require a state preparation and has the advantage that it admits noisy measurements. We also report a successful experiment performed according to our idea. In the case of entropic Bell inequalities we show that it is more suitable to use the Tsallis entropy than the Shannon entropy, because it reveals non-classicality for a larger set of quantum states. Moreover, we present a new application of a method that is used to derive entropic Bell inequalities to find new bounds on the correlation between non-commuting observables.