2-A Cosmological Model with Varying G and ∧ in General Relativity

Harpreet  , R. K. Tiwari, H. S. Sahota

Department of Applied Sciences , Sant Baba Bhag Singh Institute of Engineering & Technology, Jalandhar, India.
Goverment Engineering College, Reva, M.P., India.

DOI: 10.4236/ojapps.2013.31B1015                

Abstract

Spatially homogeneous and anisotropic Cosmological models play a significant role in the description of the early stages of evolution of the universe. The problem of the cosmological constant is still unsettled. The authors recently considered time dependent G and L with Bianchi type–I Cosmological model .We considered in this paper homogeneous Bianchi type -I space-time with variable G and L containing matter in the form of a perfect fluid assuming the cosmological term proportional to R^-2 (where R is scale factor). Initially the model has a point type singularity, gravitational constant G (t) is decreasing and cosmological constant L is infinite at this time. When time increases L decreases. Unlike in some earlier works we have neither assumed equation of state nor particular form of G. The model does not approach isotropy, if ‘t’ is small .The model is quasi-isotropic for large value of ‘t’.

Keywords

Bianchi Type-I Universe; Varying G and ∧ ; Cosmology

Conflicts of Interest

The authors declare no conflicts of interest.

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