N-density representability and the optimal transport limit of the Hohenberg-Kohn functional
N-density representability and the optimal transport limit of the Hohenberg-Kohn functional
We derive and analyze a hierarchy of approximations to the strongly correlated limit of the Hohenberg-Kohn functional. These "density representability approximations" are obtained by first noting that in the strongly correlated limit, N-representability of the pair density reduces to the requirement that the pair density must come from a symmetric …