Interactions in the dark sector within the scope of Bianchi type-V model

We are building a cosmological model that has small anisotropy and curvature. For this purpose, the Bianchi type-V (BV) model with dark matter (DM) and anisotropic dark energy (DE) is considered. Assuming a law for deviation from the equation of state (Eos) of DE is linear, we study the transition from decelerated to late accelerated expansion of the Universe. In the proposed model, the linear interaction of the two components alleviates the coincidence problem of the present Universe. Examples of model parameter values compatible with observational data are given.

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Exact vacuum solutions to modified Einstein field equations in f(R) gravity

Modern Physics Letters A ◽

10.1142/s0217732320502053 ◽

2020 ◽

Vol 35 (25) ◽

pp. 2050205

Author(s):

Usamah S. Al-Ali ◽

Ashfaque H. Bokhari

Keyword(s):

Bianchi Type ◽

Constant Scalar Curvature ◽

Vacuum Field ◽

Initial Singularity ◽

De Sitter ◽

Field Equations ◽

Plane Symmetric ◽

Expansion Of The Universe ◽

Type V ◽

Bianchi Type V

Considering the plane symmetric non-static spacetimes in the context of [Formula: see text] gravity, we obtain exact solutions of the vacuum field equations by assuming constant scalar curvature. By suitable transformations, it is shown that the obtained solutions can be transformed to Bianchi type [Formula: see text], a type of Taub’s and the De Sitter solutions. Of particular interest is a solution that represents a model that has initial singularity and under an appropriate transformation can be converted to a Bianchi-type V model. This solution, like the Bianchi type V model, leads to predictions about evolution in the sense of an expanding universe starting from an initial singularity. In this context, we show that the expansion of the universe in [Formula: see text] gravity can be explained without invoking the cosmological constant [Formula: see text].

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Domain walls and quark matter in Bianchi type-V universe with observational constraints in F(R,T) gravity

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887820500140 ◽

2019 ◽

Vol 17 (01) ◽

pp. 2050014 ◽

Cited By ~ 2

Author(s):

Dinesh Chandra Maurya ◽

Anirudh Pradhan ◽

Archana Dixit

Keyword(s):

Quark Matter ◽

Domain Walls ◽

Bianchi Type ◽

Momentum Tensor ◽

Accelerated Expansion ◽

Observational Constraints ◽

Field Equations ◽

Bianchi Type V Universe ◽

Type V ◽

Bianchi Type V

In this study, we investigate the Bianchi type-V cosmological models with quark matter (QM) distribution and domain walls with observational constraints in [Formula: see text] theory of gravity (Harko et al. in Phys. Rev. D 84 (2011) 024020), for a specific choice of the function [Formula: see text] (where [Formula: see text] is Ricci scalar and [Formula: see text] is the trace of the energy–momentum tensor). We have used model-independent methods and hyperbolic expansion scale factors to achieve the deterministic solution of the modified Einstein field equations and these are also tested observationally. The behaviors of QM and domain walls give an idea of accelerated expansion of the Universe which agrees with recent observations of Type Ia Supernovae. We also discuss the physical implications of the derived models.

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

Astrophysics and Space Science ◽

10.1007/s10509-011-0745-3 ◽

2011 ◽

Vol 335 (2) ◽

pp. 565-575 ◽

Cited By ~ 71

Author(s):

Anil Kumar Yadav

Keyword(s):

Dark Energy ◽

Bianchi Type ◽

Space Time ◽

Anisotropic Dark Energy ◽

Energy Models ◽

Type V ◽

Bianchi Type V

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Dynamics of Bianchi type-V anisotropic dark energy cosmological model in a scale covariant theory of gravitation

International Journal of Mathematics and Systems Science ◽

10.24294/ijmss.v1i4.560 ◽

2018 ◽

Vol 1 (3) ◽

Author(s):

Dandala Radhakrishna Reddy 1

Keyword(s):

Dark Energy ◽

Cosmological Model ◽

Bianchi Type ◽

Covariant Theory ◽

Scale Covariant Theory ◽

Anisotropic Dark Energy ◽

Theory Of Gravitation ◽

Type V ◽

The Universe ◽

Bianchi Type V

This paper is devoted to the discussion of dynamical properties of anisotropic dark energy cosmological model of the universe in a Bianchi type-V space time in the framework of scale covariant theory of gravitation formulated by Canuto et al.(phys.Rev.Lett.39:429,1977).A dark energy cosmological model is presented by solving the field equations of this theory by using some physically viable conditions. The dynamics of the model is studied by computing the cosmological parameters, dark energy density, equation of state(EoS) parameter, skewness parameters, deceleration parameter and the jerk parameter. This being a scalar field model gives us the quintessence model of the universe which describes a significant dark energy candidate of our accelerating universe. All the physical quantities discussed are in agreement with the recent cosmological observations.

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Some Bianchi type-V accelerating cosmological models in f(R,T) = f1(R) + f2(T) formalism

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887820501595 ◽

2020 ◽

Vol 17 (10) ◽

pp. 2050159

Author(s):

Vinod Kumar Bhardwaj ◽

Anil Kumar Yadav

Keyword(s):

Phase Transition ◽

Bianchi Type ◽

Cosmological Models ◽

Accelerated Expansion ◽

Field Equations ◽

Geometrical Properties ◽

Energy Scenario ◽

Type V ◽

The Universe ◽

Bianchi Type V

In this paper, we have studied the transition and physical behavior of Bianchi type-V cosmological models within the formalism of [Formula: see text] gravity. To obtain the solution of field equations and phase transition of universe consistent with recent cosmological observations, time varying deceleration parameters are considered. In this paper, we used two different scale factors of the form (i) [Formula: see text], where [Formula: see text] are constants. Here, for [Formula: see text] the universe shows transition with accelerated expansion. (ii) [Formula: see text], where [Formula: see text] and [Formula: see text] are constants. For [Formula: see text], the universe achieves a phase transition from early decelerating to current accelerating phase. The model I initially starts with quintessence scenario ([Formula: see text]) and ends up with ([Formula: see text]) as a model with cosmological constant ([Formula: see text]) as [Formula: see text]. Model II, for [Formula: see text] indicates the phantom energy scenario and for [Formula: see text], the model starts with quintessence [Formula: see text] and ends with vacuum energy scenario. A point type singularity has been observed in the derived model I. Some physical and geometrical properties of the models have been established and discussed to derive the validity of models with respect to recent astrophysical observations.

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