Holographic dark energy with the sign-changeable interaction term

TL;DR

This paper explores holographic dark energy models with different IR cutoffs in a universe with sign-changeable interaction between dark energy and dark matter, showing some models align well with observations and can explain cosmic acceleration.

Contribution

It introduces three holographic dark energy models with various IR cutoffs considering a sign-changeable interaction, analyzing their cosmological evolution and observational consistency.

Findings

Models with Hubble cutoff interacting with dark matter are observationally viable.

Future event horizon and GO cutoff models fit well with data.

Some models allow the equation of state to cross the phantom line.

Abstract

We use three IR cutoffs, including the future event horizon, the Hubble and Granda-Oliveros (GO) cutoffs, to construct three holographic models of dark energy. Additionally, we consider a Friedmann-Robertson-Walker (FRW) universe filled by a dark matter (DM) and a dark energy that interact with each other through a mutual sign-changeable interaction. Thereinafter, we address the evolution of the some cosmological parameters, such as the equation of state and dimensionless density parameters of dark energy as well as the deceleration parameter, during the cosmic evolution from the matter dominated era until the late time acceleration. We observe that a holographic dark energy (HDE) model with Hubble cutoff interacting with DM may be in line with the current universe. Our study shows that models with the future event horizon as the IR cutoff or the GO cutoff are in good agreement with the observational data. In fact, we find out that these obtained models can predict the universe transition from a deceleration phase to the acceleration one in a compatible way with observations. The three obtained models may also allow the equation of state parameter to cross the phantom line, a result which depends on the values of the system's constants such as the value of the interaction coupling constant.