Black holes vs. firewalls and thermo-field dynamics

TL;DR

This paper explores how the thermo-field dynamics of black holes relate to the black holes vs. firewalls debate, proposing that the thermo-field doubled CFT reflects the heat-bath, influencing the presence of firewalls or smooth horizons.

Contribution

It offers a new interpretation of the thermo-field doubled CFT as the heat-bath image, differing from prior views, and links the strength of CFT-heat bath coupling to firewall presence.

Findings

Strong coupling allows free infall and describes a black hole.

Weak coupling corresponds to firewall presence.

The interpretation impacts understanding of black hole horizons.

Abstract

In this essay, we examine the implications of the ongoing black holes vs. firewalls debate for the thermo-field dynamics of black holes by analyzing a CFT in a thermal state in the context of AdS/CFT. We argue that the themo-field doubled copy of the thermal CFT should be thought of not as a fictitious system, but as the image of the CFT in the heat-bath. While this idea was proposed earlier by Papadodimas et al., our following conclusions differ from theirs. In case of strong coupling between the CFT and the heat-bath this image allows for free infall through the horizon and the system is described by a black hole. Conversely, firewalls are the appropriate dual description in case of weak interaction of the CFT with its heat bath.