Bianchi Type- I Viscous Fluid Accelerating Cosmological Models with Time Dependent Q and Λ - Term

Dinkar Singh Chauhan; R.S.Singh; Anirudh Pradhan

doi:https://doi.org/10.14445/22315373/IJMTT-V55P524

International Journal of Mathematics Trends and Technology

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Volume 55 | Number 3 | Year 2018 | Article Id. IJMTT-V55P524 | DOI : https://doi.org/10.14445/22315373/IJMTT-V55P524

Bianchi Type- I Viscous Fluid Accelerating Cosmological Models with Time Dependent Q and Λ - Term

Dinkar Singh Chauhan, R.S.Singh, Anirudh Pradhan

Abstract

In present paper, exact solutions of Einstein's field equations are obtained in a spatially homogenous and anisotropic Bianchi type-I space-time in presence of a dissipative fluid with constant and time dependent cosmological term. Einstein's field equations are solved by considering a scale factor a(t)=tet which yields a time dependent deceleration parameter that affords a late time acceleration in the universe. The cosmological constant () is found to be a decreasing function of time and it approaches a small positive value at the present epoch which is corroborated by consequences from recent supernova Ia observations. To get the deterministic solution a barotropic equation of state together with the shear viscosity is proportional to expansion scalar, is also assumed. The physical and geometric properties of cosmological models are also discussed.

Keywords

Bianchi type-I universe, variable deceleration parameters, Dissipative fluid.

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Citation :

Dinkar Singh Chauhan, R.S.Singh, Anirudh Pradhan, "Bianchi Type- I Viscous Fluid Accelerating Cosmological Models with Time Dependent Q and Λ - Term," International Journal of Mathematics Trends and Technology (IJMTT), vol. 55, no. 3, pp. 185-195, 2018. Crossref, https://doi.org/10.14445/22315373/IJMTT-V55P524