IAS Quantum Aspects of Black Holes Group Meeting

Abstract: I will review the status of the duality between type II string theory on $AdS_3 \times S^3 \times T^4$ and a specific N=(4,4) supersymmetric 2d CFT. I will begin by reviewing the understanding of this theory from the late '90s, from the points of view of supergravity, string theory, the dual CFT, and U-duality. I will then review the more recent understanding of the free limit of the CFT and its dual string theory. I will discuss work in progress (in collaboration with Gaberdiel, Kalloor and Urbach) about some questions related to this limit, and how they are answered.