AdS/CFT duality and the black hole information paradox

TL;DR

This paper explores the AdS/CFT duality in the context of near-extremal black holes, demonstrating how dual geometries relate to CFT states and analyzing the breakdown of semiclassical approximation in resolving the black hole information paradox.

Contribution

It provides a detailed correspondence between black hole microstates and dual geometries, and relates the breakdown of semiclassical evolution to the black hole information paradox.

Findings

Dual geometries have throats ending in states characterized by the CFT.

Propagation in the throat matches CFT excitations below the black hole threshold.

Semiclassical evolution breaks down when hypersurfaces stretch beyond a maximum volume.

Abstract

Near-extremal black holes are obtained by exciting the Ramond sector of the D1-D5 CFT, where the ground state is highly degenerate. We find that the dual geometries for these ground states have throats that end in a way that is characterized by the CFT state. Below the black hole threshold we find a detailed agreement between propagation in the throat and excitations of the CFT. We study the breakdown of the semiclassical approximation and relate the results to the proposal of gr-qc/0007011 for resolving the information paradox: semiclassical evolution breaks down if hypersurfaces stretch too much during an evolution. We find that a volume V stretches to a maximum throat depth of V/2G.