The holographic dark energy in non-flat Brans-Dicke cosmology

TL;DR

This study explores holographic dark energy within non-flat Brans-Dicke cosmology, finding constraints on the equation of state parameter and establishing a link to phantom dark energy models.

Contribution

It provides the first analysis of holographic dark energy in non-flat Brans-Dicke cosmology and connects it to phantom dark energy models.

Findings

Lower bound of w_Λ is -0.9, preventing crossing -1.

Holographic dark energy cannot produce phantom-like behavior in this framework.

A correspondence between flat universe holographic dark energy and phantom models is proposed.

Abstract

In this paper we study cosmological application of holographic dark energy density in the Brans-Dicke framework. We employ the holographic model of dark energy to obtain the equation of state for the holographic energy density in non-flat (closed) universe enclosed by the event horizon measured from the sphere of horizon named $L$. Our calculation show, taking $\Omega_{\Lambda}=0.73$ for the present time, the lower bound of $w_{\rm \Lambda}$ is -0.9. Therefore it is impossible to have $w_{\rm \Lambda}$ crossing -1. This implies that one can not generate phantom-like equation of state from a holographic dark energy model in non-flat universe in the Brans-Dicke cosmology framework. In the other hand, we suggest a correspondence between the holographic dark energy scenario in flat universe and the phantom dark energy model in framework of Brans-Dicke theory with potential.