The spatially homogeneous Bianchi type spacetimes

2010 ◽  
pp. 99-112
Author(s):  
Jerzy Plebanski ◽  
Andrzej Krasinski
Keyword(s):  
Bianchi Type ◽  
Spatially Homogeneous

scholarly journals Anisotropic magnetized holographic Ricci dark energy cosmological models

2017 ◽  
Vol 95 (4) ◽  
pp. 381-392 ◽  
Author(s):  
M. Vijaya Santhi ◽  
V.U.M. Rao ◽  
Y. Aditya
Keyword(s):  
General Relativity ◽  
Dark Energy ◽  
Deceleration Parameter ◽  
Bianchi Type ◽  
Cosmological Models ◽  
Field Equations ◽  
Ricci Dark Energy ◽  
Theor Phys ◽  
Linearly Varying Deceleration Parameter ◽  
Spatially Homogeneous

In this paper, we have considered spatially homogeneous and anisotropic Bianchi type-III space–time filled with matter and anisotropic modified holographic Ricci dark energy in general relativity. We have solved Einstein’s field equations using the following possibilities: (i) hybrid expansion law proposed by Akarsu et al. (JCAP, 01, 022 (2014)); (ii) a varying deceleration parameter considered by Mishra et al. (Int. J. Theor. Phys. 52, 2546 (2013)); and (iii) a linearly varying deceleration parameter given by Akarsu and Dereli (Int. J. Theor. Phys. 51, 612 (2012)). We have presented the cosmological models in each of the preceding cases and studied their evolutions. We have also discussed physical and kinematical properties of the models.

scholarly journals Chaotic inflation in spatially homogeneous Bianchi type V space–time

2017 ◽  
Vol 95 (12) ◽  
pp. 1267-1270
Author(s):  
Raj Bali ◽  
P. Kumari
Keyword(s):  
Bianchi Type ◽  
Space Time ◽  
Late Time ◽  
De Sitter ◽  
Spatially Homogeneous ◽  
Inflationary Parameters ◽  
Type V ◽  
The Universe ◽  
Anisotropic Phase ◽  
Bianchi Type V

Chaotic inflationary scenario in spatially homogeneous Bianchi type V space–time following Linde (Phys. Lett. B, 129, 177 (1983). doi: 10.1016/0370-2693(83)90837-7 ) and the condition [Formula: see text] based on theory of super cooling during the cosmological phase transition proposed by Kirzhnits and Linde (Ann. Phys. 101, 195 (1976). doi: 10.1016/0003-4916(76)90279-7 ), is discussed. It has been found that the model represents anisotropic phase of the Universe in general but at late time, it isotropizes. The deceleration parameter q = −1 indicates that the model leads to de Sitter space–time. It is found that inflationary parameters, namely, slow roll parameters, and anisotropic parameters are in excellent agreement with the Planck Collaboration’s 2013 results (Astron. Astrophys. 571, A22 (2014). doi: 10.1051/0004-6361/201321569 ).

scholarly journals Causal heat flow in Bianchi type-V Universe

2014 ◽  
Vol 29 (13) ◽  
pp. 1450071
Author(s):  
M. Govender ◽  
S. Thirukkanesh
Keyword(s):  
Temperature Profile ◽  
Bianchi Type ◽  
Irreversible Thermodynamics ◽  
Hydrostatic Equilibrium ◽  
Rotationally Symmetric ◽  
Spatially Homogeneous ◽  
Bianchi Type V Universe ◽  
Type V ◽  
Bianchi Type V

In this paper, we investigate the role of causal heat transport in a spatially homogeneous, locally-rotationally symmetric (LRS) Bianchi type-V cosmological model. In particular, the causal temperature profile of the cosmological fluid is obtained within the framework of extended irreversible thermodynamics. We demonstrate that relaxational effects can alter the temperature profile when the cosmological fluid is out of hydrostatic equilibrium.

scholarly journals LRS Bianchi type-I cosmological model with constant deceleration parameter in f(R,T) gravity

2017 ◽  
Vol 14 (11) ◽  
pp. 1750158 ◽  
Author(s):  
Binaya K. Bishi ◽  
S. K. J. Pacif ◽  
P. K. Sahoo ◽  
G. P. Singh
Keyword(s):  
Cosmological Model ◽  
Deceleration Parameter ◽  
Hubble Parameter ◽  
Bianchi Type ◽  
Specific Model ◽  
Type I ◽  
Hubble’S Parameter ◽  
Constant Deceleration Parameter ◽  
Bianchi Type I ◽  
Spatially Homogeneous

A spatially homogeneous anisotropic LRS Bianchi type-I cosmological model is studied in [Formula: see text] gravity with a special form of Hubble's parameter, which leads to constant deceleration parameter. The parameters involved in the considered form of Hubble parameter can be tuned to match, our models with the [Formula: see text]CDM model. With the present observed value of the deceleration parameter, we have discussed physical and kinematical properties of a specific model. Moreover, we have discussed the cosmological distances for our model.

On a Bianchi type-I space-time with bulk viscosity in f(R,T) gravity

2021 ◽  
Author(s):  
M. Koussour ◽  
M. Bennai
Keyword(s):  
Deceleration Parameter ◽  
Bianchi Type ◽  
Momentum Tensor ◽  
Energy Conditions ◽  
Type I ◽  
Field Equations ◽  
Bulk Fluid ◽  
Bianchi Type I ◽  
Deceleration Phase ◽  
Spatially Homogeneous

In this paper, we present a spatially homogeneous and anisotropic Bianchi type-I cosmological model with a viscous bulk fluid in [Formula: see text] gravity where [Formula: see text] and [Formula: see text] are the Ricci scalar and trace of the energy-momentum tensor, respectively. The field equations are solved explicitly using the hybrid law of the scale factor, which is related to the average Hubble parameter and gives a time-varying deceleration parameter (DP). We found the deceleration parameter describing two phases in the universe, the early deceleration phase [Formula: see text] and the current acceleration phase [Formula: see text]. We have calculated some physical and geometric properties and their graphs, whether in terms of time or redshift. Note that for our model, the bulk viscous pressure [Formula: see text] is negative and the energy density [Formula: see text] is positive. The energy conditions and the [Formula: see text] analysis for our spatially homogeneous and anisotropic Bianchi type-I model are also discussed.

scholarly journals ACCELERATING DARK ENERGY MODELS IN BIANCHI TYPE-V SPACETIME

2011 ◽  
Vol 26 (30) ◽  
pp. 2261-2275 ◽  
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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