Ángel Rincón — Page 3

arXiv2018

Relativistic dust accretion onto a scale--dependent polytropic black hole

In this work we study steady and spherical relativistic dust accretion onto a static and spherically symmetric scale--dependent black hole. In particular we consider a polytropic scale--dependent black hole as a central object and obtain that the radial velocity profile and the energy density are affected when scale--dependence of the central object is taken into account and such a deviation is controlled by the so called running parameters of the scale--dependence models.

gr-qc↗

arXiv2018

Growth index and statefinder diagnostic of Oscillating Dark Energy

We study is some detail the Cosmology of Oscillating Dark Energy described by concrete equations-of-state investigated recently in the literature. In particular, at the background level we compute the statefinder parameters, while at the level of linear cosmological perturbations we compute the growth index $γ$ as well as the combination parameter $A=f σ_8$. The comparison with $Λ$CDM is made as well.

astro-ph.CO↗

arXiv2018

Gravitational decoupled anisotropies in compact stars

Simple generic extensions of isotropic Durgapal--Fuloria stars to the anisotropic domain are presented. These anisotropic solutions are obtained by guided minimal deformations over a self gravitating isotropic system. When the isotropic and the anisotropic sector interacts in a purely gravitational manner, the conditions to decouple both sectors by means of the minimal geometric deformation approach are satisfied. Hence the anisotropic field equations are isolated resulting a more treatable set. The simplicity of the equations allows one to manipulate the anisotropies that can be implemented in a systematic way to obtain different realistic models for anisotropic configurations. Later on, observational effects of such anisotropies when measuring the redshift are discussed. To conclude, the application of the method over anisotropic solutions is generalized. In this manner, different anisotropic sectors can be isolated of each other and modeled in a simple and systematic way. Besides, a generic property of the minimal geometric deformation approach, its noncommutativity, is discussed. This property duplicates the solutions obtained through this approach; anisotropies applied in the reversed order give different physically acceptable configurations.

gr-qc↗