scholarly journals Some geometrical aspects of Bianchi type-I space time

2002 ◽  
pp. 79-86
Author(s):  
G. Mohanty ◽  
R.C. Sahu ◽  
P.K. Sahoo
Keyword(s):  
Bianchi Type ◽  
Space Time ◽  
Type I ◽  
Einstein Theory ◽  
Bianchi Type I ◽  
Spatially Homogeneous

A problem of spatially homogeneous Bianchi type-I space-time is investigated in Einstein theory without source of gravitation. Some geometrical natures of the space-time are discussed.

scholarly journals de Sitter expansion with anisotropic fluid in Bianchi type-I space-time

2010 ◽  
Vol 326 (2) ◽  
pp. 315-322 ◽  
Author(s):  
Özgür Akarsu ◽  
Can Battal Kılınç
Keyword(s):  
Bianchi Type ◽  
Space Time ◽  
Anisotropic Fluid ◽  
Type I ◽  
De Sitter ◽  
Bianchi Type I

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.

scholarly journals Higher Dimensional Bianchi Type-I Cosmological Models With Massive String in General Relativity

2021 ◽  
Vol 8 ◽  
Author(s):  
Kangujam Priyokumar Singh ◽  
Jiten Baro ◽  
Asem Jotin Meitei
Keyword(s):  
General Relativity ◽  
Bianchi Type ◽  
Early Stage ◽  
Dimensional Space ◽  
Space Time ◽  
Cosmological Models ◽  
Type I ◽  
Bianchi Type I ◽  
Geometrical Properties ◽  
Dimensional Space Time

Here we studied Bianchi type-I cosmological models with massive strings in general relativity in five dimensional space time. Out of the two different cases obtained here, one case leads to a five dimensional Bianchi type-I string cosmological model in general relativity while the other yields the vacuum Universe in general relativity in five dimensional space time. The physical and geometrical properties of the model Universe are studied and compared with the present day’s observational findings. It is observed that our model is anisotropic, expanding, shearing, and decelerates at an early stage and then accelerates at a later time. The model expands along x, y, and z axes and the extra dimension contracts and becomes unobservable at t → ∞. We also observed that the sum of the energy density (ρ) and the string tension density (λ) vanishes (ρ + λ = 0).

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 Approximate Solutions of the LRS Bianchi Type-I Cosmological Model

Symmetry ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 403
Author(s):  
Yihu Feng ◽  
Lei Hou
Keyword(s):  
Cosmological Model ◽  
Homotopy Perturbation Method ◽  
Bianchi Type ◽  
Approximate Solutions ◽  
Space Time ◽  
Type I ◽  
Main Field ◽  
Field Equations ◽  
Bianchi Type I ◽  
Homotopy Perturbation

In this current study, we explore the modified homogeneous cosmological model in the background of LRS Bianchi type-I space–time. For this purpose, we employ the Homotopy Perturbation Method (HPM). HPM is an analytical-based method. Further, we calculated the main field equations of the cosmological model LRS Bianchi type-I space–time. Furthermore, we discuss the necessary calculations of HPM. Therefore, we investigate the analytical solution of our problem by adopting HPM. In this response, we discuss five different values of parameter n. We also give a brief discussion about solutions. The main purpose of this study is to apply the application of HPM in the cosmological field.

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