Oscillatory null singularity inside realistic spinning black holes

TL;DR

This paper analyzes the behavior of curvature near the inner horizon of spinning black holes, revealing an oscillatory divergence caused by frame dragging, contrasting with spherical black hole singularities.

Contribution

It provides the first detailed calculation of the oscillatory divergence of curvature scalars at the null singularity inside realistic spinning black holes.

Findings

Curvature scalar oscillates infinitely while diverging near the singularity.

Oscillatory behavior is driven by frame dragging effects.

Contrasts with monotonic mass-inflation singularity in spherical black holes.

Abstract

We calculate the asymptotic behavior of the curvature scalar $(Riemann)^2$ near the null weak singularity at the inner horizon of a generic spinning black hole, and show that this scalar oscillates infinite number of times while diverging. The dominant parallelly-propagated Riemann components oscillate in a similar manner. This oscillatory behavior, which is in a remarkable contrast to the monotonic mass-inflation singularity in spherical charged black holes, is caused by the dragging of inertial frames due to the black- hole's spin.