English

Gravitational Collapse in Scale-Dependent Gravity

General Relativity and Quantum Cosmology 2025-04-07 v2 High Energy Astrophysical Phenomena High Energy Physics - Theory

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\om-parameter) and by scale-dependent gravity (negative \om\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.

Keywords

Cite

@article{arxiv.2410.15904,
  title  = {Gravitational Collapse in Scale-Dependent Gravity},
  author = {Ramin Hassannejad and Gaetano Lambiase and Fabio Scardigli and Fatimah Shojai},
  journal= {arXiv preprint arXiv:2410.15904},
  year   = {2025}
}

Comments

29 pages, 23 figures

R2 v1 2026-06-28T19:29:31.984Z