Radiating black holes in Einstein-Yang-Mills theory and cosmic censorship

TL;DR

This paper derives a new higher-dimensional Einstein-Yang-Mills Vaidya solution showing that YM gauge charge influences black hole horizons and can lead to naked singularities, challenging cosmic censorship.

Contribution

It presents an exact nonstatic spherically symmetric black-hole solution with YM gauge charge in higher dimensions, highlighting its effects on horizons and singularities.

Findings

YM gauge charge has an attractive gravitational effect.

Naked singularities can form, violating cosmic censorship.

YM charge reduces the initial data space for naked singularities.

Abstract

Exact nonstatic spherically symmetric black-hole solution of the higher dimensional Einstein-Yang-Mills equations for a null dust with Yang-Mills gauge charge are obtained by employing Wu-Yang \textit{ansatz}, namely, HD-EYM Vaidya solution. It is interesting to note that gravitational contribution of YM gauge charge for this ansatz is indeed opposite (attractive rather than repulsive) that of Maxwell charge. It turns out that the gravitational collapse of null dust with YM gauge charge admit strong curvature shell focusing naked singularities violating cosmic censorship. However, there is significant shrinkage of the initial data space for a naked singularity of the HD-Vaidya collapse due to presence of YM gauge charge. The effect of YM gauge charge on structure and location of the apparent and event horizons is also discussed.