Isolating the decay rate of cosmological gravitational potential

	Isolating the decay rate of cosmological gravitational potential
	Zhang, Pengjie
刊名	ASTROPHYSICAL JOURNAL
	2006-08-10
卷号	647 期号:1 页码:55-59
关键词	cosmic microwave background gravitational lensing large-scale structure of universe
英文摘要	The decay rate of cosmological gravitational potential measures the deviation from Einstein-de Sitter universe and can put strong constraints on the nature of dark energy and gravity. The usual method to measure this decay rate is through the integrated Sachs-Wolfe (ISW) effect-large-scale structure (LSS) cross-correlation. However, the interpretation of the measured correlation signal is complicated by galaxy bias and the matter power spectrum. This could bias and/or degrade its constraints on the nature of dark energy and gravity. But combining the lensing-LSS cross-correlation measurements, the decay rate of gravitational potential can be isolated. For any given narrow redshift bin of LSS, the ratio of the two cross-correlations directly measures (d ln D-phi/d ln a) H(z)/W(chi, chi(s)), where D-phi is the linear growth factor of the gravitational potential, H is the Hubble constant at redshift z, W(chi; chi(s)) is the lensing kernel, and chi and chi(s) are the comoving angular diameter distance to lens and source, respectively. This method is optimal in the sense that (1) the measured quantity is essentially free of systematic errors and is only limited by cosmic variance, and (2) the measured quantity depends only on several cosmological parameters and can be predicted from first principles unambiguously. Although fundamentally limited by the inevitably large cosmic variance associated with the ISW measurements, it can still put useful independent constraints on the amount of dark energy and its equation of state. It can also provide a powerful test of modified gravity and can distinguish the Dvali-Gabadadze-Porrati model from Lambda CDM at > 2.5 sigma confidence level.
学科主题	星系和宇宙学研究中心
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	INTEGRATED SACHS-WOLFE ; LARGE-SCALE STRUCTURE ; CROSS-CORRELATION ; MICROWAVE ; GALAXIES ; GRAVITY ; WMAP
收录类别	SCI
语种	英语
WOS记录号	WOS:000239647800005
公开日期	2010-11-08
内容类型	期刊论文
源URL	[http://119.78.226.72//handle/331011/11925]
专题	上海天文台_星系宇宙学重点实验室
作者单位	Chinese Acad Sci, Shanghai Astron Observ, Shanghai 200030, Peoples R China
推荐引用方式 GB/T 7714	Zhang, Pengjie. Isolating the decay rate of cosmological gravitational potential[J]. ASTROPHYSICAL JOURNAL,2006,647(1):55-59.
APA	Zhang, Pengjie.(2006).Isolating the decay rate of cosmological gravitational potential.ASTROPHYSICAL JOURNAL,647(1),55-59.
MLA	Zhang, Pengjie."Isolating the decay rate of cosmological gravitational potential".ASTROPHYSICAL JOURNAL 647.1(2006):55-59.