Infinite symmetry prevents disorder-induced localization in 2D

We show that 2D gapped many-body quantum states are constrained by an infinite-dimensional symmetry which renders them transparent to weak disorder. This prevents disorder-induced localization when interactions are strong enough to open a gap. Using purely algebraic methods we derive all possible quantum states near the superconductor-to-insulator (SIT) transition and we compute the meson spectrum of superinsulators.