Order Parameters and Color-Flavor Center Symmetry in QCD

Common lore suggests that Ncolor QCD with massive quarks has no useful order parameters which can be non-trivial at zero baryon density. However, such order parameters do exist when there are n_fquark flavors with a common mass and d\equiv\gcd(n_f,N) > 1 These theories have a \mathbb Z_dcolor-flavor center symmetry arising from intertwined color center transformations and cyclic flavor permutations. The symmetry realization depends...