Dark energy perturbations revisited

	Dark energy perturbations revisited
	Li, MZ; Cai YF(蔡一夫); Li H(李虹); Zhang XM(张新民); Cai, YF; Li, H; Brandenberger, R; Zhang, XM
刊名	PHYSICS LETTERS B
	2011
卷号	702 期号:1 页码:5-11
关键词	Dark energy Cosmological perturbations
通讯作者	[Li, Mingzhe] Nanjing Univ, Dept Phys, Nanjing 210093, Peoples R China ; [Cai, Yifu ; Li, Hong ; Zhang, Xinmin] Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China ; [Brandenberger, Robert] McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada ; [Li, Mingzhe] Nanjing Univ, Purple Mt Observ, Joint Ctr Particle Nucl Phys & Cosmol, Nanjing 210093, Peoples R China ; [Li, Mingzhe ; Li, Hong ; Zhang, Xinmin] Chinese Acad Sci, Theoret Phys Ctr Sci Facil, Beijing 100049, Peoples R China ; [Cai, Yifu] Arizona State Univ, Dept Phys, Tempe, AZ 85287 USA
英文摘要	In this Letter we study the evolution of cosmological perturbations in the presence of dynamical dark energy, and revisit the issue of dark energy perturbations. For a generally parameterized equation of state (EoS) such as w(D) (z) = w(0) + w(1) z/1+z (for a single fluid or a single scalar field), the dark energy perturbation diverges when its EoS crosses the cosmological constant boundary w(D) = -1. In this Letter we present a method of treating the dark energy perturbations during the crossing of the w(D) = -1 surface by imposing matching conditions which require the induced 3-metric on the hypersurface of w(D) = -1 and its extrinsic curvature to be continuous. These matching conditions have been used widely in the literature to study perturbations in various models of early universe physics, such as Inflation, the Pre-Big-Bang and Ekpyrotic scenarios, and bouncing cosmologies. In all of these cases the EoS undergoes a sudden change. Through a detailed analysis of the matching conditions, we show that delta(D) and theta(D) are continuous on the matching hypersurface. This justifies the method used (Zhao et al., 2005, 2007; Xia et al., 2006, 2008) [1-4] in the numerical calculation and data fitting for the determination of cosmological parameters. We discuss the conditions under which our analysis is applicable. (C) 2011 Elsevier B.V. All rights reserved.
学科主题	Physics
类目[WOS]	Physics, Multidisciplinary
研究领域[WOS]	Physics
原文出处	SCI
语种	英语
WOS记录号	WOS:000294142600002
内容类型	期刊论文
源URL	[http://ir.ihep.ac.cn/handle/311005/236787]
专题	高能物理研究所_理论物理室高能物理研究所_粒子天体物理中心高能物理研究所_多学科研究中心
作者单位	中国科学院高能物理研究所
推荐引用方式 GB/T 7714	Li, MZ,Cai YF,Li H,et al. Dark energy perturbations revisited[J]. PHYSICS LETTERS B,2011,702(1):5-11.
APA	Li, MZ.,蔡一夫.,李虹.,张新民.,Cai, YF.,...&Zhang, XM.(2011).Dark energy perturbations revisited.PHYSICS LETTERS B,702(1),5-11.
MLA	Li, MZ,et al."Dark energy perturbations revisited".PHYSICS LETTERS B 702.1(2011):5-11.