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Open Access Research Article

Dynamics of Bianchi Type-III models with time-dependent gravitational and cosmological constants

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pp. 81–98Vol. 23Issue 1 & 2November 2025DOI: 10.47974/JDSGT-2025-01001XML
Received:
07 Jan 2025
Published Online:
29 Nov 2025
Article type:
Research Article
Language:
EN
Article no.:
JDSGT-2025-01001
Pages:
81–98

Abstract

We analyze the Einstein field equations with variable cosmological and gravitational constants, in the context of a Bianchi type-III universe filled with a perfect fluid. Here the tacit assumption is that the energy-momentum tensor obeys the conservation law.   Exact solutions to the EF equations are derived by employing the condition that the scalar of expansion is proportional to the shear scalar, θ ∝ σ, which leads to a relationship between the metric potentials given by b = cm, assuming m as a constant. The corresponding physical and graphical implications of the cosmological solutions are also investigated.

Keywords

Subject Classifications

83C0583C1583F05

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