Causal Structure of Singularity in non-spherical Gravitational Collapse

TL;DR

This paper studies the gravitational collapse of a non-spherical dust cloud, revealing that a naked singularity can form near the boundary, differing from spherical collapse, with implications for cosmic censorship.

Contribution

It demonstrates the formation of a directionally globally naked singularity near the boundary in non-spherical collapse, expanding understanding beyond spherical models.

Findings

Naked singularity forms near the boundary, not at the center.

Singularity is a strong curvature singularity per Tipler criterion.

Null geodesics are less scattered in certain directions.

Abstract

We investigate here the final state of gravitational collapse of a non-spherical and non-marginally bound dust cloud as modeled by the Szekeres spacetime. We show that a directionally globally naked singularity can be formed in this case near the collapsing cloud boundary, and not at its geometric center as is typically the case for a spherical gravitational collapse. This is a strong curvature naked singularity in the sense of Tipler criterion on gravitational strength. The null geodesics escaping from the singularity would be less scattered in this case in certain directions since the singularity is close to the boundary of the cloud as is the case in the current scenario. The physical implications are pointed out.