Singularity deep inside the spherical charged black hole core

TL;DR

This paper provides an analytical description of the spacelike singularity inside a charged black hole with a scalar field, validated by numerical simulations, revealing a strong scalar-curvature singularity connected to a weak null singularity.

Contribution

It introduces a formal series solution for the singularity inside a charged black hole with a scalar field, validated by numerical simulations, advancing understanding of black hole interior structures.

Findings

Analytical series solution matches numerical singularity behavior

Identifies a strong scalar-curvature spacelike singularity

Connects the spacelike singularity to a weak null singularity at late times

Abstract

We study analytically the spacelike singularity inside a spherically-symmetric, charged black hole coupled to a self-gravitating spherical massless scalar field. We assume spatial homogeneity, and find a generic solution in terms of a formal series expansion. This solution is tested against fully-nonlinear and inhomogeneous numerical simulations. We find full compliance between our analytical solution and the pointwise behavior of the singularity in the numerical simulations. This is a strong scalar-curvature monotonic spacelike singularity, which connects to a weak null singularity at asymptotically-late advanced time.