The Black Hole Interior in AdS/CFT and the Information Paradox

TL;DR

This work argues that black hole interiors can be described within AdS/CFT by introducing state-dependent mirror operators in the boundary theory. By constructing interior observables that act on a given CFT state $|\Psi\rangle$ (and its descendants) and leveraging a Tomita-Takesaki-type modular framework, the authors achieve a smooth horizon and reconcile unitary evaporation with locality in effective field theory. They demonstrate this for equilibrium and near-equilibrium states, providing explicit operator constructions and showing that low-point correlators remain EFT-like while fully unitary dynamics are preserved. The approach resolves several information-paradox arguments, including strong subadditivity and firewall-type critiques, and extends to non-equilibrium scenarios, highlighting the crucial role of state dependence in quantum gravity. Overall, the paper substantiates interior locality in AdS/CFT through a concrete, state-dependent interior operator construction with broad implications for holography and quantum gravity.

Abstract

We show that, within the AdS/CFT correspondence, recent formulations of the information paradox can be reduced to a question about the existence of certain kinds of operators in the CFT. We describe a remarkably simple construction of these operators on a given state of the CFT. Our construction leads to a smooth horizon, addresses the strong subadditivity paradox, while preserving locality within effective field theory, and reconciles the existence of the interior with the growth of states with energy in the CFT. We also extend our construction to non-equilibrium states.