arXiv subjects

Sudhir Kumar Srivastav

Publications and source records attributed to Sudhir Kumar Srivastav.

2 recordsLinked to original sources

arXiv2003

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

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.

gr-qc↗

arXiv2003

Some Inhomogeneous Magnetized Viscous Fluid Cosmological Models with Varying $Λ$

Some cylindrically symmetric inhomogeneous viscous fluid cosmological models with electro-magnetic field are obtained. 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. Without assumin g any {\it ad hoc} law, we obtain a cosmological constant as a decreasing function of time. The behaviour of the electro-magnetic field tensor together with some p hysical aspects of the model are also discussed.

gr-qc↗