Black Hole Complementarity vs. Locality

TL;DR

This paper challenges the assumption of locality in black hole physics, showing that string theory predicts nonlocal effects across the event horizon, which could impact the understanding of information loss in black hole evaporation.

Contribution

It provides evidence that string theory introduces nonlocal correlations across the event horizon, questioning the local quantum field theory assumption in black hole information paradox.

Findings

String theory predicts large commutators across the horizon for certain observers.

Nonlocal effects are significant only under extreme kinematic conditions.

Space-like separated operators are suppressed in Minkowski space within string theory.

Abstract

The evaporation of a large mass black hole can be described throughout most of its lifetime by a low-energy effective theory defined on a suitably chosen set of smooth spacelike hypersurfaces. The conventional argument for information loss rests on the assumption that the effective theory is a local quantum field theory. We present evidence that this assumption fails in the context of string theory. The commutator of operators in light-front string theory, corresponding to certain low-energy observers on opposite sides of the event horizon, remains large even when these observers are spacelike separated by a macroscopic distance. This suggests that degrees of freedom inside a black hole should not be viewed as independent from those outside the event horizon. These nonlocal effects are only significant under extreme kinematic circumstances, such as in the high-redshift geometry of a black hole. Commutators of space-like separated operators corresponding to ordinary low-energy observers in Minkowski space are strongly suppressed in string theory.