Breaking parameter degeneracy in interacting dark energy models from observations

TL;DR

This paper investigates how to distinguish interacting dark energy models with varying equations of state using observational data, addressing parameter degeneracies and providing tighter constraints on dark sector interactions.

Contribution

It introduces methods to break degeneracies among dark sector parameters and offers new constraints based on recent observational data.

Findings

Degeneracy among dark sector parameters identified

Global fitting constrains dark sector interaction strength

Proposes observational strategies to distinguish models

Abstract

We study the interacting dark energy model with time varying dark energy equation of state. We examine the stability in the perturbation formalism and the degeneracy among the coupling between dark sectors, the time-dependent dark energy equation of state and dark matter abundance in the cosmic microwave background radiation. Further we discuss the possible ways to break such degeneracy by doing global fitting using the latest observational data and we get a tight constraint on the interaction between dark sectors.