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北美退伍军人节(Veterans Day),12 日无更新
arXiv 1107.2628astro-ph.COgr-qc
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暗能量参数模型的标量场描述

Scalar field description of a parametric model of dark energy

E. M. Barboza, J. S. Alcaniz, B. Santos

摘要:

我们研究了暗能量状态方程(EoS)$w(z)$的含时参数化的理论和观测方面,它是整个宇宙演化过程中红移$z$的良好函数,即,$z \in [-1,\infty)$。通过使用直接从有效EoS参数构造精华势的理论算法,我们推导并讨论了该$w(z)$函数的所得势的一般特征。由于这里讨论的参数化允许我们在定义的区域划分参数平面与不同类别的暗能量模型,我们使用最新的观测Ia型超新星,重子声学振荡峰和宇宙微波背景位移参数检查哪一类是观测首选。我们表明,最大部分的置信度轮廓线位于对应于一个可能的交叉点的所谓的幻影分界线在宇宙演化的某个点的区域。

英文摘要:

We investigate theoretical and observational aspects of a time-dependent parameterization for the dark energy equation of state (EoS) $w(z)$, which is a well behaved function of the redshift $z$ over the entire cosmological evolution, i.e., $z \in [-1,\infty)$. By using a theoretical algorithm of constructing the quintessence potential directly from the effective EoS parameter, we derive and discuss the general features of the resulting potential for this $w(z)$ function. Since the parameterization here discussed allows us to divide the parametric plane in defined regions associated to distinct classes of dark energy models, we use the most recent observations from type Ia supernovae, baryon acoustic oscillation peak and Cosmic Microwave Background shift parameter to check which class is observationally prefered. We show that the largest portion of the confidence contours lies into the region corresponding to a possible crossing of the so-called phanton divide line at some point of the cosmic evolution.

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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