ABSTRACT
In the Brussels’ operational-realistic approach to cognition, concepts are treated as entities that can be in different states and be subjected to measurements performed by human minds. The Brussels group also considered two other examples of bipartite systems, the famous Bohm-EPR state of two spin-1/2 particles forming a singlet state (microscopic level) and a model of breakable elastic bands (macroscopic level) to show that they violate Bell-CHSH inequalities. Sandeau et al. employed entangled states of classical Maxwell fields coupling the polarization and spatial parity degrees of freedom in order to implement the analogue of non-unitary transformations, leading to maximal correlations beyond Tsirelson’s bound. Their approach relies on the realization at the level of classical Maxwell fields of a so-called positive operator valued measure. POVM stands for ‘positive operator valued measure’. They are the most general kinds of measurement. In standard quantum mechanics one uses ideal measurements which are one-dimensional projection operators.
