Double null formulation of the general Vaidya metric

TL;DR

This paper derives field equations for a dynamic, charged, spherically symmetric black hole in n-dimensions using double null coordinates, facilitating perturbative analysis and horizon studies.

Contribution

It introduces a double null coordinate formulation for the charged Vaidya metric in arbitrary dimensions, enhancing analytical tools for black hole dynamics.

Findings

Derived field equations for non-stationary charged black holes

Analyzed properties of apparent and event horizons

Provided a framework useful for perturbative studies

Abstract

We present here the field equations describing a non-stationary spherically symmetric n-dimensional charged black hole with varying mass m(v) and/or electric charge q(v), described by a generic charged Vaidya metric with cosmological constant Lambda in double null coordinates. This formulation of the metric has been shown to be particularly useful for perturbative studies and it was used in some recent works. Here we also discuss some issues related to the apparent and event horizons of the black hole.