Flowing Funnels: Heat sources for field theories and the AdS_3 dual of CFT_2 Hawking radiation

TL;DR

This paper constructs smooth 2+1D AdS_3 solutions dual to stationary 1+1 CFT states on black hole backgrounds, modeling heat transport and Hawking radiation in the holographic framework.

Contribution

It provides the first explicit construction of smooth bulk geometries dual to CFT states with heat flow on black hole backgrounds, including Unruh states.

Findings

Bulk solutions are smooth and diffeomorphic to AdS_3.

Unruh states correspond to extreme horizons in the bulk.

The solutions model heat transport and Hawking radiation holographically.

Abstract

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.