Quintessence and tachyon dark energy in interaction with dark matter: Observational constraints and model selection

TL;DR

This paper develops two models of interacting dark energy, based on quintessence and tachyon fields, constrained by observational data, and finds strong evidence supporting interaction over noninteracting models.

Contribution

It introduces new scalar field models of interacting dark energy with potentials derived from agegraphic dark energy, tested against multiple cosmological datasets.

Findings

Interacting models are favored over noninteracting and ΛCDM models.

Coupling constants are statistically significant at over 3σ confidence.

Models fit observational data better according to AIC and BIC criteria.

Abstract

We derive two field theory models of interacting dark energy, one in which dark energy is associated with the quintessence and another in which it is associated with the tachyon. In both, instead of choosing arbitrarily the potential of scalar fields, these are specified implicitly by imposing that the dark energy fields must behave as the new agegraphic dark energy. The resulting models are compared with the Pantheon supernovae sample, CMB distance information from Planck 2015 data, baryonic acoustic oscillations (BAO) and Hubble parameter data. For comparison, the noninteracting case and the $\Lambda CDM$ model also are considered. By use of the $ AIC $ and $ BIC $ criteria, we obtain strong evidence in favor of the two interacting models, and the coupling constants are nonvanishing at more than $3\sigma$ confidence level.