Phantom crossing dark energy in Horndeski's theory

TL;DR

This paper explores models within Horndeski's theory that allow for phantom crossing dark energy, aiming to resolve the H0 tension while avoiding instabilities common in phantom models.

Contribution

It introduces a framework for constructing stable phantom crossing dark energy models within Horndeski's theory that align with observational data.

Findings

Developed general solutions for stable phantom crossing

Constructed specific models consistent with observations

Addressed the H0 tension with new dark energy models

Abstract

The $\Lambda$CDM model is a remarkably successful model which is consistent with the observations of cosmic microwave background radiation (CMB), baryon acoustic oscillation (BAO), and large scale structure of the Universe. However, the discrepancy in the value of $H_0$ between the local observations and PLANCK observation of CMB was recently pointed out. One of the way to ease the discrepancy is to introduce phantom dark energy instead of the cosmological constant. While, phantom dark energy often suffer from the instabilities. We will investigate the general solution to overcome the difficulty of phantom dark energy and construct some particular models which have a phantom crossing and can be consistent with the observations.