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arXiv · 1204.3620

Cosmological constant dominated transit universe from early deceleration to current acceleration phase in Bianchi-V space-time

Anil Kumar Yadav
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Abstract

The paper presents the transition of universe from early decelerating phase to current accelerating phase with viscous fluid and time dependent cosmological constant $(Λ)$ as source of matter in Bianchi-V space-time. To study the transit behaviour of universe, we have assumed the scale factor as increasing function of time which generates a time dependent deceleration parameter (DP). The study reveals that the cosmological term does not change its fundamental nature for $ξ$ = constant and $ξ=ξ(t)$, where $ξ$ is the coefficient of bulk viscosity. The $Λ(t)$ is found to be positive and is decreasing function of time. The same is observed by recent supernovae observations. The physical behaviour of universe has been discussed in detail.

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Anil Kumar Yadav. 2012-04-16. Cosmological constant dominated transit universe from early deceleration to current acceleration phase in Bianchi-V space-time. https://doi.org/10.1088/0256-307x%2F29%2F7%2F079801

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