Seminar 13. Quasi-probability representations of quantum mechanics

In this seminar, we discussed quasi-probabilistic representations of quantum mechanics. Quasi-probabilistic representations are described using the frame formalism, with the properties of preparation or measurement non-contextuality of the ontological model corresponding to the positivity of the synthesis or analysis operators. There are no representations that describe quantum mechanics with zero negativity, otherwise such a frame would specify a non-contextual representation of quantum mechanics. Quasi-probabilistic representations can be used in quantum computing problems: by passing to a quasi-probabilistic representation, it is possible to make a statistical sampling of outcomes, and the complexity of such an approach grows exponentially with increasing negativity.