Interior dynamics of neutral and charged black holes

TL;DR

This study investigates the interior dynamics of neutral and charged black holes through numerical simulations of scalar collapses, revealing mass inflation phenomena near singularities and horizons, and connecting these to strong gravity dynamics.

Contribution

It provides new insights into mass inflation near singularities and horizons, combining numerical and analytical methods to explore black hole interior dynamics.

Findings

Mass inflation occurs near the central singularity in neutral scalar collapse.

Mass inflation also takes place near the inner horizons of Reissner-Nordstrom black holes.

Analytic expressions for different types of mass inflation are partially derived.

Abstract

In this paper, we explore the interior dynamics of neutral and charged black holes. Scalar collapses in flat, Schwarzschild, and Reissner-Nordstrom geometries are simulated. We examine the dynamics in the vicinities of the central singularity of a Schwarzschild black hole and of the inner horizon of a Reissner-Nordstrom black hole. In simulating scalar collapses in Schwarzschild and Reissner-Nordstrom geometries, Kruskal and Kruskal-like coordinates are used, respectively, with the presence of a scalar field being taken into account. It is found that, besides near the inner horizons of Reissner-Nordstrom and Kerr black holes, mass inflation also takes place near the central singularity in neutral scalar collapse. Approximate analytic expressions for different types of mass inflation are partially obtained via a close interplay between numerical and analytical approaches and an examination of the connections between Schwarzschild black holes, Reissner-Nordstrom black holes, neutral collapse, and charge scattering. We argue that the mass inflations near the central singularity and the inner horizon are related to the localness of the dynamics in strong gravity regions. This is in accord with the Belinskii, Khalatnikov, and Lifshitz conjecture.