# Gravitational collapse in f(R) theories

@article{Cembranos2012GravitationalCI, title={Gravitational collapse in f(R) theories}, author={Jos{\'e} Alberto Ruiz Cembranos and Alvaro de la Cruz-Dombriz and Barbara Rosario Montes Nu{\~n}ez}, journal={Journal of Cosmology and Astroparticle Physics}, year={2012}, volume={2012}, pages={021-021} }

We study the gravitational collapse in modified gravitational theories. In particular, we analyze a general f(R) model with uniformly collapsing cloud of self-gravitating dust particles. This analysis shares analogies with the formation of large-scale structures in the early Universe and with the formation of stars in a molecular cloud experiencing gravitational collapse. In the same way, this investigation can be used as a first approximation to the modification that stellar objects can suffer… Expand

#### 89 Citations

Gravitational Dust Collapse in f (R) Gravity

- Physics
- 2015

This paper is devoted to investigate gravitational collapse of dust in metric f(R) gravity. We take FRW metric for the interior region while the Schwarzchild spacetime is considered for the exterior… Expand

Collapsing spherical stars in f(R) gravity

- Physics
- 2014

We perform a careful investigation of the problem of physically realistic gravitational collapse of massive stars in f(R)-gravity. We show that the extra matching conditions that arise in the… Expand

Charged cylindrical collapse in f(𝒢) gravity

- Physics
- Modern Physics Letters A
- 2019

The aim of this paper is to study the gravitational collapse of charged cylindrical star in [Formula: see text] gravity. For this purpose, we derive dynamical equations by applying Misner–Sharp… Expand

Gravitational contraction and curvature singularities in $f(R)$ gravity

- Physics
- 2013

The discovery of the accelerated expansion of the Universe has had a vast resonance on a number of physical disciplines. In recent years a few viable modified gravity models have been proposed, which… Expand

Gravitational collapse of massless scalar field in $f(R)$ gravity

- Physics
- 2016

We study the spherically symmetric gravitational collapse of massless scalar matter field in asymptotic flat spacetime in the Starobinsky ${R}^{2}$ gravity, one specific model in the $f(R)$ gravity.… Expand

f(R) Gravity and Spherical Collapse

- Physics
- 2014

This thesis studies f(R) model building, cosmological dynamics, Solar System tests of f(R) gravity, and spherical collapse in f(R) gravity. We apply the running coupling idea to gravity. We describe… Expand

On dynamical instability of spherical star in f(R,T) gravity

- Physics
- 2015

This work is based on stability analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment in f(R,T) gravity, where R is Ricci scalar and T corresponds to the… Expand

On the collapse in fourth order gravities

- Physics
- 2012

The gravitational collapse in fourth order theories of gravity defined by an arbitrary action of the scalar curvature shows significant deviations with General Relativity. The presence of a new… Expand

Conformally flat collapsing stars in f(R) gravity

- Physics
- General Relativity and Gravitation
- 2018

The present work includes an analytical investigation of a collapsing spherical star in f(R) gravity. The interior of the collapsing star admits a conformal flatness. Information regarding the fate… Expand

Charged cylindrically symmetric collapse in f(R) gravity

- Physics
- 2017

Abstract.This paper investigates the charged cylindrically symmetric gravitational collapse with perfect fluid in f(R) gravity. We formulate dynamical equations using the Misner-Sharp formalism and… Expand

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