Bootstrapping line defects in AdS${}_3$/CFT${}_2$

Abstract

We study correlators of insertions along 1/2 BPS line defects in the holographic dual to type IIB string theory in $Ad{S}_3\times S^3\times T^4$ with mixed Ramond-Ramond and Neveu Schwarz-Neveu Schwarz three-form flux. These defects break the symmetries of the bulk CFT${}_2$ as $PSU(1,1|2{)}^2\times SO(4)\to PSU(1,1|2)\times SU(2)$, defining displacement and tilt supermultiplets. We focus on the two-, three- and four-point functions of these supermultiplets, which we compute using analytic conformal bootstrap up to next-to-leading order in their strong-coupling expansion. We obtain a bootstrap result that only depends on two OPE coefficients. We perform a Witten diagram check of the bootstrap result, obtaining an holographic interpretation of the two OPE coefficients that are not constrained by the bootstrap procedure.

41 pages, 3 figures; v2: minor changes, references added, version published in JHEP