Comment on three-point function in AdS(3)/CFT(2)
Abstract
Recently, exact agreement has been found between bulk and boundary three-point functions in AdS3 x S3 x T4 with NSNS fluxes. This represents a non-trivial check of AdS/CFT correspondence beyond the supergravity approximation as it corresponds to an exact worldsheet computation. When taking a closer look at this computation, one notices that a crucial point for the bulk-boundary agreement to hold is an intriguing mutual cancellation between worldsheet contributions corresponding to the AdS3 and to the S3 pieces of the geometry, what results in a simple factorized form for the final three-point function. In this note we review this cancellation and clarify some points about the analytic relation between the SU(2) and the SL(2,R) structure constants. In particular, we dicuss the connection to the Coulomb gas representation. We also make some comments on the four-point function.