Boundary conformal field theory at large charge

A bstract We study operators with large internal charge in boundary conformal field theories (BCFTs) symmetries. Using the state-operator correspondence and existence of a macroscopic limit, we find non-trivial relation between scaling dimension lowest dimensional CFT BCFT charged to leading order charge. also construct superfluid effective theory for boundaries use it systematically calculate spectrum systematic expansion. verify explicitly many predictions from EFT analysis concrete examples including classical scalar | ? 6 interaction three dimensions O (2) Wilson-Fisher model near four presence boundaries. In appendices additionally discuss background approach towards Ward identities general defect theories, clarify its Noether’s theorem perturbative theories.