Some remarks on Bianchi type-II, VIII, and IX models
- 80 Downloads
Within the scope of anisotropic non-diagonal Bianchi type-II, VIII, and IX spacetimes it is shown that the off-diagonal components of the Einstein equations impose severe restrictions on the components of the energy-momentum tensor (EMT) in general. We begin with a metric with three functions of time, a(t), b(t), and c(t), and two spatial ones, f(z) and h(z). It is shown that if the EMT is assumed to be diagonal, and f = f(z), in all cosmological models in question b ∝ c, and the matter distribution is isotropic, i.e., T 1 1 = T 2 2 = T 3 3 . If f = const, which is a special case of BII models, the matter distribution may be anisotropic, but only the z axis is distinguished, and in this case b(t) is not necessarily proportional to c(t).
KeywordsCosmological Model Einstein Equation SAHA Cosmic String Matter Distribution
Unable to display preview. Download preview PDF.
- 9.S. Kumar,Mod. Phys. Lett. A 26, 779 (2011).Google Scholar
- 24.Yu. P. Rybakov, G. N. Shikin, Yu. A. Popov, and B. Saha, arXiv: 1008.2113; The materials of the Russian School “Mathematical Modeling in Systems of Computer Mathematics” and the Russian Seminar “Nonlinear Fields in Gravitation and Cosmology,” Yalchik-Kazan (2010), pp. 148–153.Google Scholar