Generalized holographic dark energy and cosmic coincidence

In this work, we study a generalized interacting holographic dark energy model (GIHDEM) with a parameterized coupling constant in the spatially flat universe filled with the holographic dark energy (HDE) and dark matter (DM). More specifically, we introduce a new coupling parameter (z)between HDE and DM as a function of redshift zwhich is parameterized by the well-known Chevalier-Polarski-Linder (CPL) parameterization and Wetterich one unlike other works. Our study shows that, for both parameterizations, there is a transition from a deceleration phase to an accelerated one for the universe which is in agreement with recent observations. It has been obtained that the present coincidence parameter value (-0.37) in GIHDEM with suitable choice of the coupling parameter.

Automated summary

This study examines a generalized interacting holographic dark energy model with a parameterized coupling constant in a spatially flat universe filled with holographic dark energy and dark matter. The research findings indicate a transition from a deceleration phase to an accelerated phase for the universe under different parameterizations, and a present coincidence parameter value of -0.37 in this model with a suitable choice of the coupling parameter.