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Gravitation and Cosmology

, Volume 19, Issue 1, pp 65–69 | Cite as

Some remarks on Bianchi type-II, VIII, and IX models

  • Bijan SahaEmail author
Article

Abstract

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 bc, 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).

Keywords

Cosmological Model Einstein Equation SAHA Cosmic String Matter Distribution 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Pleiades Publishing, Ltd. 2013

Authors and Affiliations

  1. 1.Laboratory of Information TechnologiesJoint Institute for Nuclear ResearchDubna, Moscow regionRussia

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