LRS Bianchi type I models with anisotropic dark energy and constant deceleration parameter

Abstract

Locally rotationally symmetric Bianchi type I cosmological models are examined in the presence of dynamically anisotropic dark energy and perfect fluid. We assume that the dark energy (DE) is minimally interacting, has dynamical energy density, anisotropic equation of state parameter (EoS). The conservation of the energymomentum tensor of the DE is assumed to consist of two separately additive conserved parts. A special law is assumed for the deviation from isotropic EoS, which is consistent with the assumption on the conservation of the energy-momentum tensor of the DE. Exact solutions of Einstein's field equations are obtained by assuming a special law of variation for the mean Hubble parameter, which yields a constant value of the deceleration parameter. Geometrical and kinematic properties of the models and the behaviour of the anisotropy of the dark energy have been carried out. The models give dynamically anisotropic expansion history for the universe that allows to fine tune the isotropization of the Bianchi metric, hence the CMB anisotropy.

Some anisotropic dark energy models in Bianchi type-V space-time

“…Leon and Sarikadis (2010) have investigated that anisotropic geometries in modified gravitational frameworks present radically difference cosmological behaviors comparing to the simple isotropic scenarios. Akarsu et al (2010) In this paper, we have studied some physically realistic and totally anisotropic Bianchi-V models with anisotropic DE and perfect fluid. To study the anisotropic nature of DE, we have assumed the time dependent skewness parameter, which modify EoS.…”

The Measurement of and in Bianchi Type-I Anisotropic Dark Energy Cosmological Model with Constant Deceleration Parameter in Bimetric Theory of Gravitation

“…For closed universe, the Hubble parameter , H the matter energy density parameter M  and the dark energy density parameter ,   predicted by Tegmark [12] by Sahni et al [23][24].This parameter ) ( t  have been calculated with some reasoning with reduced to some simple parameterization of the dependences by many authors [25][26][27][28][29][30]. The results from SNe Ia data collaborated with CMBR anisotropy and galaxy clustering statistics (Tegmark et al [12] [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54].…”

Accelerating Dark Energy Models in Bianchi Type-v Spacetime

“…Following, Akarsu and Kilinc [37,38,50] and Yadav [21], we split the conservation of energy momentum tensor of the DE into two parts, one corresponds to deviations of EoS parameter and other is the deviation-free part of T (de)ij ;j = 0:…”

“…Setare [32]− [34] and Setare & Saridakis [35] have also studied the DE models in different contexts. Recently, dark energy models with variable EoS parameter have been studied by Ray et al [36], Akarsu and Kilinc [37,38], Yadav et al [39], Yadav and Yadav [40], Pradhan and Amirhashchi [41], Pradhan et al [42] and Amirhashchi et al [43,44]. In well-known reviews on modified gravity (Nojiri and Odintsov [45,46], it is clearly indicated that any modified gravity may be represented as effective fluid with time dependent ω.…”