Universality at large transverse spin in defect CFT
ABSTRACT :
This paper titled "Universality at large transverse spin in defect CFT" is concerned with OPE expansion of a "bulk" scalar two point function in a generic defect CFT. This two-point function can be expanded in two channels using the bulk OPE and the bulk-to-defect OPE and the crossing equation expresses the equality of these two expansions. In the light cone limit, the identity block is the leading contribution in the bulk channel. This simple universal fact in the bulk channel implies the universality of the defect spectrum at large transverse spin, via the crossing equation. We will further study the defect OPE inversion formula. OPE inversion formulas aim to obtain OPE data that contribute to a correlator by studying the poles and residues in an integral transform of the correlator. If time permits, we will study the application of these ideas in the example of the replica twist defect, which has its application in the computation of Renyi (and hence also entanglement) entropy.