Revisiting Noether gauge symmetry approach in quintom cosmology

TL;DR

This paper revisits the Noether gauge symmetry method in quintom cosmology, revealing new potential cases with nonlinear scalar field coupling and correcting previous inaccuracies in related models, thereby advancing understanding of dark energy dynamics.

Contribution

It introduces two new quintom potentials with nonlinear scalar coupling and corrects prior errors in Noether symmetry applications in cosmology.

Findings

Identified two new quintom potentials with nonlinear scalar field coupling.

Corrected inaccuracies in previous Noether gauge symmetry analyses.

Provided insights into dark energy equation of state crossing the cosmological constant boundary.

Abstract

The Noether gauge symmetry approach is revisited to study various quintom scenarios (those that arise by the presence of two dynamical scalar fields) to comprehend the role of dark energy in our universe. For such models, we obtain smooth parameterizations of the equation of state of dark energy across the boundary of cosmological constant $w_{\Lambda}=-1$. This study gives rise to two new cases of the potential $V(\phi, \sigma)$, due to a quintom field in which nonlinear coupling of the scalar fields arise. Besides we report that a few cases of Noether gauge symmetries and their invariants in [Adnan Aslam, et. al., Astrophys Space Sci (2013), 348:533-540] are incorrect. Consequently, the given cosmological model in their paper is not a feasible quintom model.