Anisotropic Cosmological Model with Variable G and Lambda

TL;DR

This paper investigates an anisotropic cosmological model with variable gravitational and cosmological constants, deriving their time evolution from the model and comparing it with current observations.

Contribution

It introduces a method to extract the time variation of G and Lambda in an anisotropic universe without assuming specific forms for these functions.

Findings

G and Lambda variations are consistent with current observations.

The model's effective equation of state parameter aligns with observational limits.

The anisotropic model provides insights into the universe's dynamics with variable constants.

Abstract

Anisotropic Bianchi-III cosmological model is investigated with variable gravitational and cosmological constants in the framework of Einstein's general relativity. The shear scalar is considered to be proportional to the expansion scalar. The dynamics of the anisotropic universe with variable G and Lambda are discussed. Without assuming any specific forms for Lambda and the metric potentials, we have tried to extract the time variation of G and Lambda from the anisotropic model. The extracted G and Lambda are in conformity with the present day observation. Basing upon the observational limits, the behaviour and range of the effective equation of state parameter are discussed.