Gravitational Collapse in Scale-Dependent Gravity

TL;DR

This paper investigates gravitational collapse in scale-dependent gravity, analyzing horizon formation and matter properties in models inspired by asymptotically safe gravity, revealing how quantum gravity effects influence black hole formation.

Contribution

It introduces a novel analysis of gravitational collapse within scale-dependent gravity frameworks, including both asymptotically safe and scale-dependent models, with detailed horizon and matter evolution.

Findings

Event and apparent horizons are studied during collapse.

Energy conditions impose constraints on the matter equation of state.

Inner and outer geometries are smoothly matched during collapse.

Abstract

In this paper we study an Oppenheimer-Snyder (OS)-like gravitational collapse in the general framework of scale-dependent gravity. We explore the collapse in spherically symmetric solutions suggested both by asymptotically safe gravity (characterized by a positive $\om$-parameter) and by scale-dependent gravity (negative $\om$-parameter), when a singularity at a finite positive radial coordinate is developed. The inner geometry of the collapsing star is described, as usual, by a spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) metric, and matter is uniformly distributed without any assumptions about its equation of state. The outer asymptotically-safe/scale-dependent black hole metric is smoothly matched to the inner geometry, and this yields the equation of motion of the star surface, the energy density, pressure, and equation of state of the collapsing matter. We study in detail the proper-time evolution of the event and apparent horizons. Finally, the constraints of the energy conditions on the equation of state, and its properties, are considered and discussed.