Signatures of Bulk Black Hole Merger from Semi-classical 2d CFT

TL;DR

This paper investigates how conical defect scattering in AdS$_3$ reveals signatures of black hole formation, showing a transition from scattering to black hole phase influenced by operator dimensions.

Contribution

It introduces a systematic approximation method for Virasoro blocks in 2d CFT to analyze black hole signatures in bulk scattering amplitudes.

Findings

Transition from scattering to black hole phase observed

Black hole signatures appear before operators surpass the BTZ mass gap

Method provides new insights into AdS/CFT correspondence in real-time processes

Abstract

We study the real-time bulk AdS$_3$ two-into-two scattering amplitude of conical defects. This is done through means of a previously developed method of systematic approximation of the monodromy problem for the Virasoro blocks of the four-point HHHH correlator in 2d CFT in the large central charge regime. We find that dialing the external scaling dimension triggers a transition from a scattering phase to an intermediate black hole phase. This transition occurs before the individual heavy operators exceed the BTZ mass gap.