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arXiv · hep-th/0701016

A String-Inspired Quintom Model Of Dark Energy

Yi-fu Cai·Mingzhe Li·Jian-Xin Lu·Yun-Song Piao·Taotao Qiu·Xinmin Zhang
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Abstract

We propose in this paper a quintom model of dark energy with a single scalar field $ϕ$ given by the lagrangian ${\cal L}=-V(ϕ)\sqrt{1-α^\prime\nabla_μϕ\nabla^μϕ+β^\prime ϕ\Boxϕ}$. In the limit of $β^\prime\to$0 our model reduces to the effective low energy lagrangian of tachyon considered in the literature. We study the cosmological evolution of this model, and show explicitly the behaviors of the equation of state crossing the cosmological constant boundary.

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Yi-fu Cai, Mingzhe Li, Jian-Xin Lu, Yun-Song Piao, Taotao Qiu, Xinmin Zhang. 2007-05-23. A String-Inspired Quintom Model Of Dark Energy. https://doi.org/10.1016/j.physletb.2007.05.056

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