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Causal Bulk Viscous LRS Bianchi I Models With Variable Gravitational and Cosmological "Constant"

Anirudh Pradhan·Purnima Pandey·G. P. Singh·R. V. Deshpandey
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Abstract

In this paper we have investigated an LRS Bianchi I anisotropic cosmological model of the universe by taking time varying $G$ and $Λ$ in the presence of bulk viscous fluid source described by full causal non-equilibrium thermodynamics. We obtain a cosmological constant as a decreasing function of time and for $m, n > 0$, the value of cosmological ``constant'' for this model is found to be small and positive which is supported by the results from recent supernovae observations.

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Anirudh Pradhan, Purnima Pandey, G. P. Singh, R. V. Deshpandey. 2005-07-23. Causal Bulk Viscous LRS Bianchi I Models With Variable Gravitational and Cosmological "Constant". https://arxiv.org/abs/gr-qc/0310023

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