Phantom cosmologies from QCD ghost dark energy

TL;DR

This paper explores a dark energy model inspired by QCD ghost fields, examining its behavior and extensions, and investigates scenarios leading to phantom regimes, singularities, and transitions to accelerated expansion.

Contribution

It introduces two novel dark energy density models inspired by holography and entropic forces, analyzing their cosmological implications and late-time behavior.

Findings

Discovery of a Type III singularity in one model

Transition from decelerated to accelerated expansion as phantom

Final universe state approaches de Sitter space

Abstract

We review a dynamical dark energy model scarcely studied in the literature and we introduce two possible generalizations. We discuss separately the behavior of the original model and a minimal extension of it by exploring some early and late times limits, we find that the cosmic components are related by their parameters state. In order to have access to the phantom regime we present two dark energy densities inspired from the holographic approach and from the emergent entropic forces model in the early universe. For the first case we obtain a Type III singularity and in the second proposal we have a transition from decelerated to accelerated cosmic expansion that starts as phantom type. However, the final stage of the universe is a de Sitter state.