A note on interacting holographic dark energy with a Hubble-scale cutoff

TL;DR

This paper investigates interacting holographic dark energy models with a Hubble-scale cutoff, finding that such models are inconsistent with observed cosmic microwave background and matter power spectra, thus challenging their viability for explaining cosmic acceleration.

Contribution

It provides a detailed analysis of phenomenological interactions in holographic dark energy models with a Hubble cutoff, showing their incompatibility with observational data.

Findings

Matter power spectrum and CMB spectra do not match observations

No viable parameter values for the interaction coupling constants

Interacting holographic dark energy with Hubble cutoff is not supported by data

Abstract

Holographic dark energy with the Hubble radius as infrared cutoff has been considered as a candidate to explain the late-time cosmic acceleration and it can solve the coincidence problem. In this scenario, a non-zero equation of state is only possible if there is an interaction between dark energy and cold dark matter. In this paper, a set of phenomenological interactions is assumed and a detailed analysis of the possible values of the coupling constants is carried out, however the resulting matter power spectrum and cosmic microwave background temperature and polarization power spectra have a shape very far from the observed ones. These results rule out any value for the free parameters and it seems to indicate that the assumed interacting holographic dark energy with a Hubble-scale cutoff is not viable to explain the accelerated expansion of the Universe, when cosmological data are taken into account.