Gravitational collapse in non-minimally coupled gravity: finite density singularities and the breaking of the no-hair theorem

TL;DR

This paper investigates gravitational collapse in a non-minimally coupled gravity model, revealing unique phenomena such as finite density black holes and violation of the no-hair theorem, differing from standard collapse outcomes.

Contribution

It introduces a detailed analysis of collapse dynamics in non-minimal coupling gravity, highlighting the impact of matter Lagrangian choice and boundary conditions on black hole properties.

Findings

Finite density black holes can form in this model.

The no-hair theorem can be broken, with black hole end states depending on initial conditions.

Distinct phenomenology compared to standard Oppenheimer-Snyder collapse.

Abstract

In this work we study the dynamics of gravitational collapse of a homogeneous dust sphere in a model exhibiting a linear non-minimal coupling between matter and curvature. The evolution of the scale factor and the matter density is obtained for different choices of Lagrangean density of matter, highlighting the direct physical relevance of the latter in this theory. Following a discussion of the junction conditions and boundary terms in the action functional, the matching with the outer metric and event horizon is analyzed. We find that a distinct phenomenology arises when compared with standard results for the Oppenheimer-Snyder collapse, namely the possibility of finite density black holes and the breaking of the no-hair theorem, due to a dependence of the end state of a black hole on the initial radius of the spherical body.