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arXiv · 1106.0416

Bulk Viscous LRS Biachi-I Universe with variable $G$ and decaying $Λ$

Anil Kumar Yadav·Anirudh Pradhan·Ajay Kumar Singh
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Abstract

The present study deals with spatially homogeneous and totally anisotropic locally rotationally symmetric (LRS) Bianchi type I cosmological model with variable $G$ and $Λ$ in presence of imperfect fluid. To get the deterministic model of Universe, we assume that the expansion $(θ)$ in the model is proportional to shear $(σ)$. This condition leads to $A=\ell B^{n}$, where $A$,\;$B$ are metric potential. The cosmological constant $Λ$ is found to be decreasing function of time and it approaches a small positive value at late time which is supported by recent Supernovae Ia (SN Ia) observations. Also it is evident that the distance modulus curve of derived model matches with observations perfectly.

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Anil Kumar Yadav, Anirudh Pradhan, Ajay Kumar Singh. 2011-07-25. Bulk Viscous LRS Biachi-I Universe with variable $G$ and decaying $Λ$. https://doi.org/10.1007/s10509-011-0814-7

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