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

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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ACCELERATING DARK ENERGY MODELS IN BIANCHI TYPE-V SPACETIME

Modern Physics Letters A ◽

10.1142/s0217732311036620 ◽

2011 ◽

Vol 26 (30) ◽

pp. 2261-2275 ◽

Cited By ~ 46

Author(s):

ANIRUDH PRADHAN ◽

HASSAN AMIRHASHCHI

Keyword(s):

Dark Energy ◽

Bianchi Type ◽

Late Time ◽

Field Equations ◽

Future Evolution ◽

New Exact Solutions ◽

Spatially Homogeneous ◽

Type V ◽

The Universe ◽

Bianchi Type V

Some new exact solutions of Einstein's field equations in a spatially homogeneous and anisotropic Bianchi type-V spacetime with minimally interaction of perfect fluid and dark energy components have been obtained. To prevail the deterministic solution we choose the scale factor [Formula: see text], which yields a time-dependent deceleration parameter (DP), representing a model which generates a transition of the universe from the early decelerating phase to the recent accelerating phase. We find that for n ≥ 1, the quintessence model is reproducible with present and expected future evolution of the universe. The other models (for n < 1), we observe the phantom scenario. The quintessence as well as phantom models approach to isotropy at late time. For different values of n, we can generate a class of physically viable DE models. The cosmic jerk parameter in our descended model is also found to be in good concordance with the recent data of astrophysical observations under appropriate condition. The physical and geometric properties of spatially homogeneous and anisotropic cosmological models are discussed.

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TILTED BIANCHI TYPE-V BAROTROPIC FLUID COSMOLOGICAL MODELS WITH VARIABLE BULK VISCOSITY IN GENERAL RELATIVITY

International Journal of Modern Physics A ◽

10.1142/s0217751x11054462 ◽

2011 ◽

Vol 26 (24) ◽

pp. 4299-4310

Author(s):

RAJ BALI ◽

PRAMILA KUMAWAT ◽

SHALINI SHARMA

Keyword(s):

General Relativity ◽

Heat Conduction ◽

Bulk Viscosity ◽

Bianchi Type ◽

Deterministic Model ◽

Cosmological Models ◽

Barotropic Fluid ◽

Type V ◽

The Universe ◽

Bianchi Type V

Tilted Bianchi type-V barotropic fluid cosmological models with heat conduction and variable bulk viscosity is investigated. To get the deterministic model of the universe, we have assumed two conditions: (i) A = (BC)nand (ii) ζθ = const where A, B, C are metric potentials, n is a constant, ζ the coefficient of bulk viscosity, θ the expansion in the model. The behavior of the model in presence and absence of bulk viscosity and singularities in the model are discussed. Some thermodynamic relations and physical aspects of the model related to the observation on the present day universe are also discussed.

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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 COSMOLOGICAL MODELS IN SCALAR–TENSOR THEORIES

Modern Physics Letters A ◽

10.1142/s0217732310033177 ◽

2010 ◽

Vol 25 (27) ◽

pp. 2363-2371 ◽

Cited By ~ 6

Author(s):

J. K. SINGH

Keyword(s):

Magnetic Field ◽

Bianchi Type ◽

Cosmological Models ◽

Energy Conditions ◽

Einstein Field Equations ◽

Field Equations ◽

Static Solutions ◽

Type V ◽

The Magnetic Field ◽

Bianchi Type V

A class of non-static solutions to the Einstein field equations has been investigated in the context of Bianchi type-V spacetime in a family of scalar–tensor theories in the presence as well as absence of the magnetic field. The physical and kinematical behaviors of the models have been discussed. The energy conditions of the models have also been verified.

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