Islands and Page curves in 4d from Type IIB

TL;DR

This paper investigates the black hole information paradox in four-dimensional string theory models, demonstrating how island contributions and Page curves emerge in these setups through holographic dualities involving branes and field theories.

Contribution

It constructs fully backreacted 10d solutions in Type IIB string theory that realize 4d gravity with baths, identifying island contributions and Page curves in these models.

Findings

Island contributions to entanglement entropy are confirmed in 4d string theory models.

Critical angles in brane configurations determine the emergence of islands.

Dual field theories exhibit parameters analogous to critical angles affecting entanglement.

Abstract

Variants of the black hole information paradox are studied in Type IIB string theory setups that realize four-dimensional gravity coupled to a bath. The setups are string theory versions of doubly-holographic Karch/Randall brane worlds, with black holes coupled to non-gravitating and gravitating baths. The 10d versions are based on fully backreacted solutions for configurations of D3, D5 and NS5 branes, and admit dual descriptions as $\mathcal N=4$ SYM on a half space and 3d $T_\rho^\sigma[SU(N)]$ SCFTs. Island contributions to the entanglement entropy of black hole radiation systems are identified through Ryu/Takayanagi surfaces and lead to Page curves. Analogs of the critical angles found in the Karch/Randall models are identified in 10d, as critical parameters in the brane configurations and dual field theories.