Role of Gauss-Bonnet corrections in a DGP brane gravitational collapse

TL;DR

This paper examines how Gauss-Bonnet corrections and DGP brane gravity influence gravitational collapse, revealing possible singularities and deviations from standard black hole formation in a brane-world context.

Contribution

It analyzes the combined effects of Gauss-Bonnet terms and DGP gravity on collapse dynamics and singularity formation, extending previous models to include higher curvature corrections.

Findings

Collapse can lead to shell-focusing or sudden singularities.

Deviations from Schwarzschild geometry can prevent black hole formation.

Naked singularities may emerge instead of black holes.

Abstract

An Oppenheimer-Snyder (OS)-type collapse is considered for a Dvali-Gabadadze-Porrati (DGP) brane, whereas a Gauss-Bonnet (GB) term is provided for the bulk. We study the combined effect of the DGP induced gravity plus the GB curvature, regarding any modification of the general relativistic OS dynamics. Our paper has a twofold objective. On the one hand, we investigate the nature of singularities that may arise at the collapse end state. It is shown that all dynamical scenarios for the contracting brane would end in one of the following cases, depending on conditions imposed: either a central shell-focusing singularity or what we designate as a "sudden collapse singularity." On the other hand, we also study the deviations of the exterior spacetime from the standard Schwarzschild geometry, which emerges in our modified OS scenario. Our purpose is to investigate whether a black hole always forms regarding this brane world model. We find situations where a naked singularity emerges instead.