Interacting generalized ghost dark energy in non-flat universe

TL;DR

This paper explores a generalized ghost dark energy model within Einstein gravity, analyzing its behavior in flat and non-flat universes, including interactions, and constrains model parameters using observational data.

Contribution

It extends the ghost dark energy model to include interactions and non-flat geometries, providing new insights into its equation of state and observational constraints.

Findings

Non-interacting model approaches de-Sitter phase with $w_D o -1$

Interacting model can cross the phantom line ($w_D < -1$)

Model parameters are constrained using SNIa, CMB, BAO, and X-ray data

Abstract

We investigate the generalized Quantum Chromodynamics (QCD) ghost model of dark energy in the framework of Einstein gravity. First, we study the non-interacting generalized ghost dark energy in a flat Friedmann-Robertson-Walker (FRW) background. We obtain the equation of state parameter, $w_D=p/\rho$, the deceleration parameter, and the evolution equation of the generalized ghost dark energy. We find that, in this case, $w_D$ cannot cross the phantom line ($w_D>-1$) and eventually the universe approaches a de-Sitter phase of expansion $(w_D\rightarrow-1)$. Then, we extend the study to the interacting ghost dark energy in both a flat and non-flat FRW universe. We find that the equation of state parameter of the interacting generalized ghost dark energy can cross the phantom line ($w_D<-1$) provided the parameters of the model are chosen suitably. Finally, we constrain the model parameters by using the Markov Chain Monte Carlo (MCMC) method and a combined dataset of SNIa, CMB, BAO and X-ray gas mass fraction.