Non-minimal quintessence and phantom with nearly flat potentials

TL;DR

This paper explores non-minimally coupled quintessence and phantom dark energy models with nearly flat potentials, showing they converge to similar behaviors and fit observational data more flexibly than minimal models.

Contribution

It provides analytical expressions for the evolution of dark energy equations of state in non-minimal coupling scenarios, highlighting richer behaviors and improved data compatibility.

Findings

Models converge to a common behavior.

Non-minimal coupling allows easier data fitting.

Less strict constraints on model parameters.

Abstract

We investigate quintessence and phantom dark energy scenarios, in which the scalar fields evolve in nearly flat potentials and are non-minimally coupled to gravity. We show that all such models converge to a common behavior and we provide the corresponding approximate analytical expressions for $w(\Omega_\phi)$ and $w(a)$. We find that non-minimal coupling leads to richer cosmological behavior comparing to its minimal counterpart. In addition, comparison with Baryon Acoustic Oscillation and latest Supernovae data reveals that agreement can be established more easily and with less strict constraints on the model parameters.