Cosmological Model with Polytropic Bulk Viscosity and Varying Gravitational and Cosmological Constants
Abstract
This paper investigates Einstein’s field equations within a cosmological model that incorporates a polytropic bulk viscous fluid, with the gravitational and cosmological constants varying in a Bianchi type-I universe. It is observed that different time-dependent scenarios yield variations in physical parameters, which hold significant implications for cosmic evolution. Key physical parameters, including energy density, the gravitational constant, expansion scalar, the cosmological constant, the bulk viscosity coefficient and shear scalar are examined for their physical significance. The geometrical and observational interpretations of the cosmological model are also investigated.
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