What is the dual of two entangled CFTs?

TL;DR

This paper challenges the traditional duality between eternal black holes and two entangled CFTs, proposing that fuzzball states and rapid tunneling alter the spacetime structure behind the horizon.

Contribution

It introduces a new perspective where the dual of two entangled CFTs is two entangled but disconnected fuzzball spacetimes, contrasting with the eternal black hole picture.

Findings

Hawking radiation entanglement complicates the duality.

Fuzzball states suggest a different dual spacetime structure.

Rapid tunneling prevents the eternal black hole from existing as a semiclassical spacetime.

Abstract

It has been conjectured that the dual of the eternal black hole in AdS is two entangled but disconnected CFTs. We show that the entanglement created by the process of Hawking radiation creates several challenges for this conjecture. The nature of fuzzball states suggests a different picture, where the dual to two entangled CFTs is two entangled but disconnected spacetimes. We argue for a process of `quick tunneling' where the Einstein-Rosen bridge of the eternal hole tunnels rapidly into fuzzball states, preventing the existence of the eternal hole as a semiclassical spacetime. The regions behind the horizon then emerge only in the approximation of fuzzball complementarity, where one considers the impact of probes with energy $E\gg T$.