Free fall onto evaporating black holes at the quantum limit

TL;DR

This paper models black hole evaporation as a quantum computational process, revealing that particles in free fall become increasingly entangled with the black hole as it slowly evaporates through discrete Hawking radiation steps.

Contribution

It introduces a quantum information perspective to black hole evaporation, linking extremal states to quantum computation limits and particle entanglement dynamics.

Findings

Black hole evaporation involves extremely high quantum computational activity.

Particles in free fall satisfy a conserved $EM=$constant$ during evaporation.

Entanglement between particles and black hole increases over time.

Abstract

Black hole space times evaporate in discrete steps due to remarkably slow Hawking radiation. We here identify evaporation with essentially extremal states at the limit of quantum computation, performing $2.7\times 10^{79}$ bit calculations per photon emission in a one solar mass black hole. During evaporation, particles in free fall co-evolve satisfying $EM=$constant, where $E$ and $M$ denote the total mass energy-at-infinity of the particle and, respectively, black hole. Particles are hereby increasingly entangled with the black hole space-time over the course of its evaporation.