Frontiers in Astronomy and Space Sciences (Aug 2022)
A cosmological model with time dependent Λ, G and viscous fluid in general relativity
Abstract
In this paper, we investigate Bianchi type − V cosmological models with bulk viscous fluid and time varying cosmological Λ and Newtonian G parameters. The Einstein’s field equations have been transformed into a coupling non-linear, first-order differential equations, and the fourth-order Runge-Kutta method of numerical integration has been used to integrate the differential equations with appropriate initial conditions consistent with current cosmological observations. We show that the model describes a universe that starts off with a negative cosmological term, as well as a matter-dominated and decelerated early epoch that, eventually becomes Λ-dominated and expanding with acceleration, in concordance with current observations.
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