An Anisotropic Kantowski–Sachs Universe with Radiation, Dust and a Phantom Fluid

被引:0
作者
G. Oliveira-Neto
D. L. Canedo
G. A. Monerat
机构
[1] Universidade Federal de Juiz de Fora,Departamento de Física, Instituto de Ciências Exatas
[2] Universidade do Estado do Rio de Janeiro,Departamento de Modelagem Computacional, Instituto Politécnico
来源
Brazilian Journal of Physics | 2022年 / 52卷
关键词
Cosmology; Anisotropic models; Isotropization; Phantom fluid; Big rip singularity;
D O I
暂无
中图分类号
学科分类号
摘要
In the present work, we study the dynamical evolution of a homogeneous and anisotropic KS cosmological model, considering general relativity as the gravitational theory, such that there are three different perfect fluids in the matter sector. They are radiation, dust and phantom fluid. Our main motivation is determining if the present model tends to a homogeneous and isotropic FRW model, during its evolution. Also, we want to establish how the parameters and initial conditions of the model, quantitatively, influence the isotropization of the present model. In order to simplify our task, we use the Misner parametrization of the KS metric. In terms of that parametrization the KS metric has two metric functions: the scale factor a(t) and β(t)\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\beta (t)$$\end{document}, which measures the spatial anisotropy of the model. We solve, numerically, the Einstein’s equations of the model and find a solution where the universe starts to expand from a small initial size and continues to expand until it ends in a Big Rip singularity. We explicitly show that for the expansive solution, after same time, the universe becomes isotropic. Based on that result, we can speculate that the expansive solution may represent an initial anisotropic stage of our Universe, that later, due to the expansion, became isotropic.
引用
收藏
相关论文
共 78 条
  • [21] Bansod AS(2016)undefined JCAP 11 188-undefined
  • [22] Wankhade RP(2018)undefined Annals Phys. 393 017-undefined
  • [23] Ajmire HG(2018)undefined Astrophys. Space Sci. 363 207-undefined
  • [24] Chaubey R(2018)undefined JCAP 11 018-undefined
  • [25] Adhav KS(2019)undefined Annals Phys. 406 021-undefined
  • [26] Parisi L(2020)undefined JCAP 07 1149-undefined
  • [27] Radicella N(2020)undefined JCAP 08 2315-undefined
  • [28] Vilasi G(2020)undefined Eur. Phys. J. C 80 3997-undefined
  • [29] Keresztes Z(1987)undefined Phys. Rev. D 35 1009-undefined
  • [30] Forsberg M(1990)undefined Phys. Rev. D 42 565-undefined