Attractor Solution in Coupled Yang-Mills Field Dark Energy Models

TL;DR

This paper studies the attractor solutions in coupled Yang-Mills dark energy models, showing they lead to a universe with de Sitter expansion and evolving dark energy equation-of-state, consistent with observations.

Contribution

It derives constraints for the interaction term in coupled Yang-Mills dark energy models and characterizes the evolution of the dark energy equation-of-state in attractor solutions.

Findings

Attractor solutions require specific interaction constraints.

Dark energy equation-of-state evolves from positive to less than or equal to -1.

Universe exhibits de Sitter expansion, avoiding the big rip.

Abstract

We investigate the attractor solution in the coupled Yang-Mills field dark energy models with the general interaction term, and obtain the constraint equations for the interaction if the attractor solution exists. The research also shows that, if the attractor solution exists, the equation-of-state of the dark energy must evolve from $w_y>0$ to $w_y\le-1$, which is slightly suggested by the observation. At the same time, the total equation-of-state in the attractor solution is $w_{tot}=-1$, the universe is a de Sitter expansion, and the cosmic big rip is naturally avoided. These features are all independent of the interacting forms.