Quantum information erasure inside black holes

TL;DR

This paper presents a lattice model for black hole infall that reproduces Hawking radiation and shows that quantum information entering the black hole is erased before reaching the singularity, supporting the idea of a smooth horizon.

Contribution

It introduces a discretized effective field theory for infalling observers that demonstrates information erasure near the singularity, aligning with black hole complementarity.

Findings

Reproduces Hawking radiation spectrum

Shows information is erased within a scrambling time

Supports smooth horizon without drama for infalling observers

Abstract

An effective field theory for infalling observers in the vicinity of a quasi-static black hole is given in terms of a freely falling lattice discretization. The lattice model successfully reproduces the thermal spectrum of outgoing Hawking radiation, as was shown by Corley and Jacobson, but can also be used to model observations made by a typical low-energy observer who enters the black hole in free fall at a prescribed time. The explicit short distance cutoff ensures that, from the viewpoint of the infalling observer, any quantum information that entered the black hole more than a scrambling time earlier has been erased by the black hole singularity. This property, combined with the requirement that outside observers need at least of order the scrambling time to extract quantum information from the black hole, ensures that a typical infalling observer does not encounter drama upon crossing the black hole horizon in a theory where black hole information is preserved for asymptotic observers.