Evolution of magnetic component in Yang-Mills condensate dark energy models

TL;DR

This paper studies how electric and magnetic components of Yang-Mills condensate evolve in dark energy models, showing electric dominance leads to a cosmological constant-like behavior, while magnetic dominance does not support dark energy.

Contribution

It provides a detailed analysis of the evolution of YM condensate components and their implications for dark energy, highlighting conditions for cosmic acceleration and coincidence problem resolution.

Findings

Electric dominance results in a cosmological constant-like behavior.

Magnetic dominance cannot serve as dark energy due to its equation of state.

YM condensate tracks radiation in early universe.

Abstract

The evolution of the electric and magnetic components in an effective Yang-Mills condensate dark energy model is investigated. If the electric field is dominant, the magnetic component disappears with the expansion of the Universe. The total YM condensate tracks the radiation in the earlier Universe, and later it becomes $w_y\sim-1$ thus is similar to the cosmological constant. So the cosmic coincidence problem can be avoided in this model. However, if the magnetic field is dominant, $w_y>1/3$ holds for all time, suggesting that it cannot be a candidate for the dark energy in this case.