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arXiv 0809.0114hep-th
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具有O($N$)对称性的Quintom模型

Quintom model with O($N$) symmetry

M. R. Setare, E. N. Saridakis

摘要:

我们研究了在广义情形下的暗能量五分模型,其中相应的正则场和幻影场具有O($N$)对称性。假设指数势,我们发现,这个O $(N)$五分之一范例表现出新的性质相比,简单的规范和幻影的情况。特别是,我们发现,宇宙不能导致一个quintessence类型的解决方案与$w>-1$,即使在幻影场似乎是无关紧要的情况下。相反,总是有晚期吸引子,它们对应于具有$w<-1$的加速宇宙和最近穿过幻影分界线的宇宙,并且对于参数空间的非常大的区域,它们是唯一的吸引子。这与以前的简单五分法结果相反,在简单五分法中,加速宇宙是一个可能的晚期稳定解,但不能保证。

英文摘要:

We investigate the quintom model of dark energy in the generalized case where the corresponding canonical and phantom fields possess O($N$) symmetries. Assuming exponential potentials we find that this O$(N)$ quintom paradigm exhibits novel properties comparing to the simple canonical and phantom scenarios. In particular, we find that the universe cannot result in a quintessence-type solution with $w>-1$, even in the cases where the phantom field seems to be irrelevant. On the contrary, there are always late-time attractors which correspond to accelerating universes with $w<-1$ and with a recent crossing of the phantom divide, and for a very large area of the parameter space they are the only ones. This is in contrast with the previous simple-quintom results, where an accelerating universe is a possible late-time stable solution but it is not guaranteed.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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