We test General Relativity (GR) using current cosmological data: the cosmic microwave background (CMB) from WMAP5 (Komatsu et al. 2009), the integrated Sachs-Wolfe (ISW) effect from the cross-correlation of the CMB with six galaxy catalogs (Giannantonio et al. 2008), a compilation of supernovae Type Ia (SNe) including the latest SDSS SNe (Kessler et al. 2009), and part of the weak lensing (WL) data from CFHTLS (Fu et al. 2008, Kilbinger et al. 2009) that probe linear and mildly non-linear scales. We first test a model where the effective Newton's constant, mu, and the ratio of the two gravitational potentials, eta, transit from the GR value to another constant at late times; in this case, we find that standard GR is fully consistent with the combined data. The strongest constraint comes from the ISW effect which would arise from this gravitational transition; the observed ISW signal imposes a tight constraint on a combination of mu and eta that characterizes the lensing potential. Next, we consider four pixels in time and space for each function mu and eta, and perform a Principal Component Analysis (PCA) finding that seven of the resulting eight eigenmodes are consistent with GR within the errors. Only one eigenmode shows a 2-sigma deviation from the GR prediction, which is likely to be due to a systematic effect. However, the detection of such a deviation demonstrates the power of our time- and scale-dependent PCA methodology when combining observations of structure formation and expansion history to test GR.
Solar system relativity tests, formulas for light deflection by a central mass, and modification of the lens equation, for a Weyl scaling invariant dark energy
Beyond general relativity: probing gravity with gravitational redshifts
Imperial College（帝国理工学院）；INAF - Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所博洛尼亚天文与空间科学观测站）；INFN - Sezione di Bologna（意大利国家核物理研究所博洛尼亚分部）；University of Ferrara（费拉拉大学）；Canadian Institute for Theoretical Astrophysics（加拿大理论天体物理研究所）；University College London（伦敦大学学院）
Probing General Relativity on Cosmological Scales in the 2040s
INFN – Istituto Nazionale di Fisica Nucleare, Sezione di Torino（意大利国家核物理研究所都灵分部）；Queen Mary University of London（伦敦玛丽女王大学）；INAF – Istituto Nazionale di Astrofisica, Osservatorio Astrofisico di Torino（意大利国家天体物理研究所都灵天文台）；University of Western Cape（西开普敦大学）；INAF – Osservatorio Astronomico di Trieste（意大利国家天体物理研究所的里雅斯特天文台）；INFN – Sezione di Trieste（意大利国家核物理研究所的里雅斯特分部）；Institute for Fundamental Physics of the Universe（宇宙基础物理研究所）；INAF – Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所博洛尼亚天文与空间科学观测站）；University College London（伦敦大学学院）；INFN – Sezione di Bologna（意大利国家核物理研究所博洛尼亚分部）；Max Planck Institute for Extraterrestrial Physics（马克斯·普朗克地外物理研究所）；Canadian Institute for Theoretical Astrophysics, University of Toronto（多伦多大学加拿大理论天体物理研究所）；CNRS/IN2P3, CPPM（法国国家科学研究中心/法国原子能和替代能源委员会粒子物理中心）；INAF – Osservatorio Astronomico di Brera（意大利国家天体物理研究所布雷拉天文台）；University of Hertfordshire（赫特福德大学）；Scuola Internazionale Superiore di Studi Avanzati (SISSA)（国际高等研究学校）；ICTP – International Centre for Theoretical Physics（国际理论物理中心）
