An Anisotropic and Spatially Homogeneous Bianchi type-ICosmological model in Saez-Ballester Cosmology Filledwith Viscous Fluid
Keywords:
Saez-Ballester theory of gravitation, Anisotropic, Bianchi type-I, Cosmological model, Petrov type-D, Spatially homogeneousAbstract
This paper presents an exact Bianchi type-I cosmological model in the Saez-Ballester scalar-tensor theory of gravitation in the presence of a viscous fluid. Assuming that the free gravitational field is of Petrov type-D, exact expressions are obtained for the metric potentials, scalar field, and several kinematical parameters. The behaviour of the spatial volume, expansion scalar, mean Hubble parameter, shear scalar, energy density, and isotropic pressure is discussed in detail. In particular, the model exhibits an initial
singularity, a finite turnover time controlled by the coefficient of viscosity, and a decay of shear with cosmic time.
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