Characterising the sets of quantum states with non-negative Wigner function

Nicolas J. Cerf, Ulysse Chabaud, Jack Davis +3

For Hilbert spaces $\mathcal{H}\subseteq L^2(\mathbb{R})$ we consider the convex sets ${\mathcal{D}}_{+}(\mathcal{H})$ of Wigner-positive states (WPS), i.e.~density matrices over $\mathcal…