Joint Theory Seminar: Ana-Maria Raclariu

Title: Infinite towers of 2d symmetry algebras from Carrollian limit of 3d CFT

Abstract: 3d Carrollian and 2d celestial conformal field theories have been proposed to capture holographic aspects of gauge theories and gravity in 4d asymptotically flat spacetimes. In this talk, I will show that this proposal can be obtained from a limit of AdS/CFT. I will consider the Carrollian limit of OPE blocks of scalar primaries, spin-1 currents and the stress tensor in 3d CFT. I will show that these OPE blocks decompose into OPE blocks of towers of sl(2,C) modes labeled by negative integer dimensions. I will discuss two applications of this construction. I will first show that the current-scalar-scalar and stress tensor-scalar-scalar OPE blocks in 3d CFT reduce to sl(2,C) OPE blocks from which towers of conformally soft photon and graviton theorems can be derived. I will then show that the 3d CFT OPE blocks of, respectively, current and stress tensor components dual to positive helicity gluons and gravitons in 4d AdS become sl(2,C) blocks of conformally soft gluons and gravitons which imply the S and w infinity algebras of celestial CFT.