A Better Way to Reconstruct Dark Energy Models ?

TL;DR

This paper explores improved methods for reconstructing dark energy models by introducing a variable matter equation of state and proposing alternative models that better align with observational data.

Contribution

It introduces a variable matter equation of state to smoothly transition between radiation and matter eras and proposes an alternative dark energy model closer to observations.

Findings

The $ ho imes a^{3}$ dark energy model aligns better with observational data.

The $ ho$ proportional model is found to be unacceptable.

A new approach to reconstruct dark energy models using $z_{eq}$ and $z_{t}$ is proposed.

Abstract

To reconstruct dark energy models the redshift $z_{eq}$, marking the end of radiation era and the beginning of matter-dominated era, can play a role as important as $z_{t}$, the redshift at which deceleration parameter experiences a signature flip. To implement the idea we propose a variable equation of state for matter that can bring a smooth transition from radiation to matter-dominated era in a single model. A popular $\Lambda \propto \rho$ dark energy model is chosen for demonstration but found to be unacceptable. An alternative $\Lambda \propto \rho a^{3}$ model is proposed and found to be more close to observation.