Scott Collier: 3d quantum gravity and Virasoro TQFT

I will discuss the quantization of one of the simplest theories of gravity, three-dimensional Einstein gravity with negative cosmological constant. In particular I will describe a precise reformulation of AdS_3 quantum gravity in terms of a novel topological quantum field theory known as "Virasoro TQFT." This proposal clarifies the relationship between pure AdS_3 quantum gravity and (two copies of) SL(2,R) Chern-Simons theory, and resolves some well-known issues with this lore. I will argue that moreover this proposal provides a practical framework for the computation of 3d gravity partition functions, and will describe how it elucidates various aspects of the holographic dual.