Two-Fluid Dark Energy Models in Bianchi Type-III Universe with Variable Deceleration Parameter

TL;DR

This paper derives new exact solutions for anisotropic Bianchi type-III universe models with dark energy and variable deceleration, showing evolution towards isotropy and consistency with observational data.

Contribution

It presents novel exact solutions for Bianchi type-III dark energy models with variable deceleration, including interaction cases and analysis of their evolution.

Findings

Dark energy EoS tends to -1 over time.

Models approach isotropy at late times.

Cosmic jerk parameter matches observations.

Abstract

Some new exact solutions of Einstein's field equations have come forth within the scope of a spatially homogeneous and anisotropic Bianchi type-III space-time filled with barotropic fluid and dark energy by considering a variable deceleration parameter. We consider the case when the dark energy is minimally coupled to the perfect fluid as well as direct interaction with it. Under the suitable condition, the anisotropic models approach to isotropic scenario. We also find that during the evolution of the universe, the equation of state (EoS) for dark energy $\omega^{(de)}$, in both cases, tends to -1 (cosmological constant, $\omega^{(de)} = -1$), by displaying various patterns as time increases, which is consistent with recent observations. The cosmic jerk parameter in our derived models are in good agreement with the recent data of astrophysical observations under appropriate condition. It is observed that the universe starts from an asymptotic Einstein static era and reaches to the $\Lambda$CDM model. So from recently developed Statefinder parameters, the behavior of different stages of the universe has been studied. The physical and geometric properties of cosmological models are also discussed.