Statefinder parameters for quantum effective Yang-Mills condensate dark energy model

TL;DR

This paper uses the Statefinder diagnostic to analyze the quantum effective Yang-Mills condensate dark energy model, showing it closely resembles the cosmological constant but with distinguishable features across different decay scenarios.

Contribution

It applies the Statefinder parameters to the YMC dark energy model in various decay cases, providing explicit trajectories and evolution profiles to differentiate it from other models.

Findings

YMC model has r ≈ 1 for z < 10

s ≈ 0 for z < 5, close to LCDM

Distinct from other dark energy models

Abstract

The quantum effective Yang-Mills condensate (YMC) dark energy model has some distinguished features that it naturally solves the coincidence problem and, at the same time, is able to give an equation of state $w$ crossing -1. In this work we further employ the Statefinder pair $(r,s)$ introduced by Sahni et al to diagnose the YMC model for three cases: the non-coupling, the YMC decaying into matter only, and the YMC decaying into both matter and radiation. The trajectories $(r,s)$ and $(r,q)$, and the evolutions $r(z)$, $s(z)$ are explicitly presented. It is found that, the YMC model in all three cases has $r\simeq 1$ for $ z < 10$ and $s\simeq 0$ for $z<5$ with only small deviations $\simeq 0.02$, quite close to the cosmological constant model (LCDM), but is obviously differentiated from other dark energy models, such as quiesence, kinessence etc.