The final state of gravitational collapse in Eddington-inspired Born-Infeld theory

TL;DR

This paper investigates gravitational collapse in Eddington-inspired Born-Infeld theory, revealing a non-singular final state and deriving a mass threshold for black hole formation with constraints on the theory's coupling parameter.

Contribution

It introduces an effective equation with first-order EiBI corrections and analyzes the exterior geometry, providing new insights into collapse outcomes in this modified gravity theory.

Findings

Non-singular, non-Schwarzschild final geometry

Mass threshold for black hole formation

Constraint on EiBI coupling parameter |7|=5.110^{-97} kg^{-1} m^3

Abstract

In this paper, we address the implications when a homogeneous dust model is considered for a scenario of gravitational collapse in the context of Eddington-inspired Born-Infeld (EiBI) theory. In order to describe the dynamical evolution of the collapse, we present an effective equation, which constitutes the first order corrections, in EiBI coupling parameter $\kappa$, to Einstein's field equations. The geometry outside the collapsing object is derived by imposing the standard Darmois-Israel junction conditions at the boundary surface of the dust. This induces an effective matter source in the outer region which gives rise to a non-singular, non-Schwarzschild geometry at the final state of the collapse. For this exterior geometry, we find the threshold of mass for the formation of the black hole. This provides a cut-off over $\kappa$ as $|\kappa|=5.1\times10^{-97} ~kg^{-1}\cdot m^3$.