Boundary conformal field theory, holography and bulk locality

Abstract: We study bulk locality in a scalar effective field theory (EFT) in AdS background in presence of an end-of-the-world (EOW) brane. The holographic dual description is given in terms of a boundary conformal field theory (BCFT). We compute the two point correlation function of scalar operators in the BCFT using the one-loop Witten diagrams and compare its analytic structure with the constraints imposed by boundary conformal symmetry. We find that the loop-corrected correlator derived from a local bulk description is not fully compatible with BCFT expectations. This result places nontrivial constraint on bulk locality in holographic BCFT constructions and identifies BCFT correlators as sensitive probes of quantum bulk dynamics in presence of boundaries.