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arXiv · 2204.09678

Anisotropic Bianchi Type V Bulk Viscous Universe with Variable G and Lambda

Nawsad Ali
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Abstract

The present study deals with spatially homogeneous and totally anisotropic Bianchi type V cosmological model in presence of bulk viscous fluid source with time dependent gravitational constant G and cosmological term Lambda. The coefficient of bulk viscosity zeta is considered to be a quadratic function of Hubble parameter H (i.e. zeta=zeta_0+zeta_1H+zeta_2H^2, where zeta_0, zeta_1 and zeta_2 are constants). Exact solution of Einstein's field equations are obtained by using a particular form of Hubble parameter H i.e. H(a)=m(a^-n +1), where m>0, n>1, a being a scale factor and H=(da/dt)/a which provides an early deceleration and late time acceleration of the universe. From state finder diagnosis {r, s} the behavior of the universe in different stages during the evolution is exhibits.

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Nawsad Ali. 2022-04-20. Anisotropic Bianchi Type V Bulk Viscous Universe with Variable G and Lambda. https://arxiv.org/abs/2204.09678

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