Flowing funnels: heat sources for field theories and the AdS3 dual of CFT2 Hawking radiation

We construct the general (2+1)-dimensional asymptotically AdS(3) solution dual to a stationary 1+1 CFT state on a black hole background. These states involve heat transport by the CFT between the 1+1 black hole and infinity (or between two 1+1 black holes), and so describe the AdS dual of CFT Hawking radiation. Although the CFT stress tensor is typically singular at the past horizon of the 1+1 black hole, the bulk (2+1)-dimensional solutions are everywhere smooth, and in fact are diffeomorphic to AdS(3). In particular, we find that Unruh states of the CFT on any finite-temperature 1+1 black hole background are described by extreme horizons in the bulk.