Interacting dark energy in the dark $SU(2)_R$ model

TL;DR

This paper investigates a dark $SU(2)_R$ model where dark energy interacts with dark matter via decay, affecting background cosmology but currently limited by parameter degeneracies in observational constraints.

Contribution

It introduces a dark $SU(2)_R$ interaction model affecting cosmological background equations, highlighting observational degeneracies and constraints.

Findings

Interaction modifies background equations compared to $\\Lambda$CDM.

Observational constraints are limited to standard cosmological parameters.

Parameter degeneracies hinder detailed observational constraints.

Abstract

We explore the cosmological implications of the interactions among the dark particles in the dark $SU(2)_R$ model. It turns out that the relevant interaction is between dark energy and dark matter, through a decay process. With respect to the standard $\Lambda$CDM model, it changes only the background equations. We note that the observational aspects of the model are dominated by degeneracies between the parameters that describe the process. Thus, only the usual $\Lambda$CDM parameters, such as the Hubble expansion rate and the dark energy density parameter (interpreted as the combination of the densities of the dark energy doublet) could be constrained by observations at this moment.