No Drama in 2D Black Hole Evaporation

TL;DR

This paper presents numerical simulations of 2D regular black hole formation and evaporation, revealing smooth horizon evaporation, complex dynamics with trapped regions, and implications for unitarity.

Contribution

It introduces a detailed numerical model of 2D black hole evaporation showing smooth horizon disappearance and rich backreaction effects.

Findings

Apparent horizons evaporate smoothly in finite time.

Anti-trapped regions form alongside black holes.

Spacetime remains singularity-free and asymptotically flat.

Abstract

We numerically calculate the spacetime describing the formation and evaporation of a regular black hole in 2D dilaton gravity. The apparent horizons evaporate smoothly in finite time to form a compact trapped region. We nevertheless see rich dynamics; an anti-trapped region forms alongside the black hole, and additional compact trapped and anti-trapped regions are formed by backreaction effects as the mass radiates away. The spacetime is asymptotically flat at future null infinity and is free of singularities and Cauchy horizons. These results suggest that the evaporation of regular 2D black holes is unitary.