English

Geodesic Congruences and a Collapsing Stellar Distribution in f (T ) Theories

General Relativity and Quantum Cosmology 2020-07-01 v1

Abstract

Teleparallel Gravity (TG) describes gravitation as a torsional- rather than curvature-based effect. As in curvature-based constructions of gravity, several different formulations can be proposed, one of which is the Teleparallel equivalent of General Relativity (TEGR) which is dynamically equivalent to GR. In this work, we explore the evolution of a spatially homogeneous collapsing stellar body in the context of two important modifications to TEGR, namely f (T) gravity which is the TG analogue of f (R) gravity, and a nonminimal coupling with a scalar field which has become popular in TG for its effects in cosmology. We explore the role of geodesic deviation to study the congruence of nearby particles in lieu of the Raychaudhuri equation. We find f (T) models that satisfy the null energy condition and describe interesting collapse profiles. In the case of a nonminimally coupled scalar field, we also find potential collapse models with intriguing scalar field evolution profiles.

Keywords

Cite

@article{arxiv.2006.05086,
  title  = {Geodesic Congruences and a Collapsing Stellar Distribution in f (T ) Theories},
  author = {Soumya Chakrabarti and Jackson Levi Said},
  journal= {arXiv preprint arXiv:2006.05086},
  year   = {2020}
}

Comments

12 pages, 5 Figures, Accepted for Publication in Physical Review D