High Energy Theory Seminar

The purpose of the talk is twofold. I will first report on progress made on the problem of finding a holographic dual of the large N=4 background AdS3xS3xS3xS1. I will discuss the BPS spectrum of the background in detail, both from a string theory and a supergravity point of view. This allows us to make a proposal for the CFT dual, at least for specific values of the fluxes.
In a second part of the talk, I will discuss the string theory spectrum on AdS3 backgrounds away from the pure NS-NS flux point, where a WZW description of the worldsheet theory exists. The theory with R-R flux can be described in the hybrid formalism by a sigma-model on a supergroup coupled to ghosts. I will explain how to solve this sigma-model in the plane-wave limit and reproduce the plane-wave spectrum from the hybrid formalism.