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Avoiding the Big-Rip Jeopardy in a Quintom Dark Energy Model with Higher Derivatives

Xiao-fei Zhang·Taotao Qiu
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Abstract

In the framework of a single scalar field quintom model with higher derivative, we construct in this paper a dark energy model of which the equation of state (EOS) $w$ crosses over the cosmological constant boundary. Interestingly during the evolution of the universe $w<-1$ happens just for a period of time with a distinguished feature that $w$ starts with a value above -1, transits into $w<-1$, then comes back to $w>-1$. This avoids the Big Rip jeopardy induced by $w<-1$.

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Xiao-fei Zhang, Taotao Qiu. 2006-12-13. Avoiding the Big-Rip Jeopardy in a Quintom Dark Energy Model with Higher Derivatives. https://doi.org/10.1016/j.physletb.2006.09.038

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