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Some Homogeneous Bianchi Type IX Viscous Fluid Cosmological Models with a varying $Λ$

Anirudh Pradhan·Sudhir Kumar Srivastav·Mahesh K. Yadav
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Abstract

Some Bianchi type IX viscous fluid cosmological models are investigated. To get a solution a supplementary condition between metric potentials is used. The viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density whereas the coefficient of shear viscosity is considered as proportional to scale of expansion in the model. The cosmological constant $Λ$ is found to be positive and is a decreasing function of time which is supported by results from recent supernova observations. Some physical and geometric properties of the models are also discussed.

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Anirudh Pradhan, Sudhir Kumar Srivastav, Mahesh K. Yadav. 2003-10-05. Some Homogeneous Bianchi Type IX Viscous Fluid Cosmological Models with a varying $Λ$. https://doi.org/10.1007/s10509-005-5832-x

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