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Cosmological Evolution of a Quintom Model of Dark Energy

Zong-Kuan Guo·Yun-Song Piao·Xinmin Zhang·Yuan-Zhong Zhang
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Abstract

We investigate in this paper the cosmological evolution of a dark energy model with two scalar fields where one of the scalar has canonical kinetic energy and another scalar has negative kinetic energy term. For such a system with exponential potentials we find that during the evolution of the universe the equation of state $w$ changes from $w>-1$ to $w<-1$, which is consistent with the recent observations. A phase-plane analysis shows that the "phantom"-dominated scaling solution is the stable late-time attractor of this type of models.

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Zong-Kuan Guo, Yun-Song Piao, Xinmin Zhang, Yuan-Zhong Zhang. 2004-10-27. Cosmological Evolution of a Quintom Model of Dark Energy. https://doi.org/10.1016/j.physletb.2005.01.017

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