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arXiv 0907.1709astro-ph.CO
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以哈勃视界为IR截止点的全息暗能量模型

Holographic Dark Energy Model with Hubble Horizon as an IR Cut-off

Lixin Xu

摘要:

本文的主要任务是在全息暗能量模型的框架下,以哈勃视界$H$作为红外截止点,实现宇宙观测相容宇宙。当一个时变宇宙学常数(CC)$Λ(t)=3c^{2}H^{2}(t)$的模型参数$c$变得依赖于时间或尺度时,一个额外的项进入真空能量$w^{eff}_Λ=-c^2-d\ln c^{2}/3d\ln a$的有效状态方程(EoS)。这一附加项可以使时间变量CC的有效EoS越过宇宙学边界,成为目前的幻影。由于缺乏第一原理和基本物理理论来获得$c^2$的形式,我们给出了一个简单的参数化形式的$c^2$作为例子。然后用宇宙观测资料对模型进行了验证,包括Ia超新星、BAO和CMB位移参数$R$。结果表明,该模型与宇宙观测结果是一致的。

英文摘要:

The main task of this paper is to realize a cosmic observational compatible universe in the framework of holographic dark energy model when the Hubble horizon $H$ is taken as the role of an IR cut-off. When the model parameter $c$ of a time variable cosmological constant (CC) $Λ(t)=3c^{2}H^{2}(t)$ becomes time or scale dependent, an extra term enters in the effective equation of sate (EoS) of the vacuum energy $w^{eff}_Λ=-c^2-d\ln c^{2}/3d\ln a$. This extra term can make the effective EoS of time variable CC cross the cosmological boundary and be phantom-like at present. For the lack of a first principle and fundamental physics theory to obtain the form $c^2$, we give a simple parameterized form of $c^2$ as an example. Then the model is confronted by the cosmic observations including SN Ia, BAO and CMB shift parameter $R$. The result shows that the model is consistent with cosmic observations.

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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