Gravitational collapse in f (R) gravity for a spherically symmetric spacetime admitting a homothetic Killing vector

Abstract

The gravitational collapse of a spherical distribution, in a class of f(R) theories of gravity, where f(R) is power function of R, is discussed. The spacetime is assumed to admit a homothetic Killing vector. In the collapsing modes, some of the situations indeed hit a singularity, but they are all covered with an apparent horizon. Some peculiar cases are observed where the collapsing body settles to a constant radius at a given value of the radial coordinate.

Gravitationally collapsing stars in f(R) gravity

“…In this appendix, we give the detail expressions of the physical quantities of the collapsing matter cloud in terms of the metric functions. More precisely, we give the values for ( 10)-( 13), and other quantities like the expansion scalar ( 8) and the Misner-Sharp mass function (27).…”

“…In the context of inhomogeneous LTB models in GR, these issues have been considered in great detail for various matter models including dust and viscous fluids [30,31]. The stellar collapse of stellar collapse in f (R) gravity using different forms of f (R) function and different matter distributions may be found in [32][33][34][35][36][37][38][39][40][41][42][43][44][45][46]. Although different type of f (R) models may be considered, only the ones which are in agreement with the standard cosmological observations should be of interest.…”

“…Although different type of f (R) models may be considered, only the ones which are in agreement with the standard cosmological observations should be of interest. Here, we consider three models of f (R) gravity given respectively by: [37] and (c) f (R) = R + λ exp (−σ R) − 1 , with λσ < 1, [48]. All three theories play a major role in the study of the early and the late universe.…”

“…However, only those f (R) models should be considered physically viable which are in agreement with the standard cosmological observations. Here, we consider two models of f (R) gravity as (a) f (R) = R + λR 2 [34] and (b) f (R) ∼ R n+1 [27]. The interior collapsing spacetime is smoothly matched with the exterior Vaidya spacetime over a timelike surface Σ [35,36].…”

Higher Dimensional Rotating Black Hole Solutions in Quadratic f(R) Gravitational Theory and the Conserved Quantities

“…The theory can describe the inflationary stage and dark energy-dominated stage, in which the late-time cosmic acceleration is realized [ 59 , 60 , 61 ]. A static spherically symmetric solution is discussed in [ 62 , 63 , 64 ], whereas studies on gravitational collapse can be found in [ 65 , 66 ]. Several black holes are derived in the framework of [ 67 , 68 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 , 77 , 78 ] and their physical consequences are discussed in [ 79 , 80 , 81 , 82 ].…”