Spherically symmetric gravitational collapse of a dust cloud in third order Lovelock Gravity

TL;DR

This paper explores how third order Lovelock gravity affects the gravitational collapse of dust clouds, revealing new types of singularities and space-time structures that differ significantly from general relativity, especially in higher dimensions.

Contribution

It introduces three families of LTB-like solutions in third order Lovelock gravity and analyzes their impact on singularity formation and cosmic censorship in higher dimensions.

Findings

High order curvature terms influence singularity nature.

Massive, naked, and time-like singularities can form in 7D.

Naked singularities in D≥8 can violate cosmic censorship.

Abstract

We investigate the spherically symmetric gravitational collapse of an incoherent dust cloud by considering a LTB type space-time in third order Lovelock Gravity without cosmological constant, and give three families of LTB-like solutions which separately corresponding to hyperbolic, parabolic and elliptic. Notice that the contribution of high order curvature corrections have a profound influence on the nature of the singularity, and the global structure of space-time changes drastically from the analogous general relativistic case. Interestingly, the presence of high order Lovelock terms leads to the formation of massive, naked and time-like singularities in the 7D space-time, which is disallowed in general relativity. Moveover, we point out that the naked singularities in the 7D case may be gravitational weak therefore may not be a serious threat to the cosmic censorship hypothesis, while the naked singularities in the $D\geq8$ inhomogeneous collapse violate the cosmic censorship hypothesis seriously.