Collapsing sphere on the brane radiates

TL;DR

This paper models a collapsing dust sphere on a brane, revealing that unlike in general relativity, it radiates null radiation due to a Vaidya radiation envelope and matches to a Reissner-Nordstrom solution.

Contribution

It introduces a brane-world collapse model showing radiation emission, contrasting with classical GR predictions, and incorporates a Vaidya radiation zone in the analysis.

Findings

The collapsing sphere has a Vaidya radiation envelope.

The solution matches a Reissner-Nordstrom metric.

The model demonstrates radiation emission during collapse.

Abstract

We study the analogue of the Oppenheimer-Snyder model of a collapsing sphere of homogeneous dust on the Randall-Sundrum type brane. We show that the collapsing sphere has the Vaidya radiation envelope which is followed by the brane analogue of the Schwarzschild solution described by the Reissner-Nordstrom metric. The collapsing solution is matched to the brane generalized Vaidya solution and which in turn is matched to the Reissner-Nordstrom metric. The mediation by the Vaidya radiation zone is the new feature introduced by the brane. Since the radiating mediation is essential, we are led to the remarkable conclusion that a collapsing sphere on the brane does indeed, in contrast to general relativity, radiate null radiation.