On the mass function at the inner horizon of a regular black hole

TL;DR

This paper reviews and compares calculations of the inner mass function of Hayward regular black holes using different approaches, analyzing scalar perturbations and contrasting with Reissner-Nordstrom black holes.

Contribution

It provides detailed derivations of the inner mass function for Hayward black holes using Ori's approach and discusses differences with Reissner-Nordstrom solutions.

Findings

Inner mass function calculations differ between approaches.

Scalar perturbation energy density near the inner horizon is quantified.

Comparison highlights distinctions between regular and singular black holes.

Abstract

Calculations of the inner mass function of the Hayward regular black hole with fluxes are reviewed and rederived. We present detailed calculations of the inner mass function in two forms of the Ori approach (the ingoing flux is continuous, the outgoing flux is modeled by a thin null shell) and compare them with calculations in Reissner-Nordstrom black hole. A formal reason of different results is discussed. The energy density of scalar perturbations propagating from the event horizon into the Hayward black hole measured by a free falling observer near the inner horizon is calculated.