Pulling Out the Island with Modular Flow

TL;DR

This paper proposes a method to extract information from the black hole interior island by manipulating radiation degrees of freedom, utilizing boundary-bulk modular flow equivalence, demonstrated with JT gravity models.

Contribution

It introduces a concrete approach to retrieve information from the black hole island using modular flow acting on radiation, with explicit examples in JT gravity.

Findings

Almost pull out an operator from the island to the bath.

Explicit bulk picture with free massless fermion fields.

Demonstrates information extraction via boundary-bulk modular flow.

Abstract

Recent works have suggested that the entanglement wedge of Hawking radiation coming from an AdS black hole, will include an island inside the black hole interior after the Page time. In this paper, we propose a concrete way to extract the information from the island by acting only on the radiation degrees of freedom, building on the equivalence between the boundary and bulk modular flow. We consider examples with black holes in JT gravity coupled to baths. In the case that the bulk conformal fields contain free massless fermion field, we provide explicit bulk picture of the information extraction process, where we find that one can almost pull out an operator from the island to the bath with modular flow.