Tension of the E_{G} statistic and redshift space distortion data with the PlanckΛ CDM model and implications for weakening gravity
Abstract
The E_{G} statistic is a powerful probe for detecting deviations from general relativity by combining weak lensing (WL), realspace clustering, and redshift space distortion (RSD) measurements, thus probing both the lensing and the growth effective Newton constants (G_{L} and G_{eff}). We construct an uptodate compilation of E_{G} statistic data including both redshift and scale dependence [E_{G}(R ,z )]. We combine this E_{G} data compilation with an uptodate compilation of f σ_{8} data from RSD observations to identify the current level of tension between the PlanckΛ CDM standard model based on general relativity and a general modelindependent redshift evolution parametrization of G_{L} and G_{eff}. Each f σ_{8} data point considered has been published separately in the context of independent analyses of distinct galaxy samples. However, there are correlations among the data points considered due to overlap of the analyzed galaxy samples. Due to these correlations, the derived levels of tension of the bestfit parameters with PlanckΛ CDM are somewhat overestimated, but this is the price to pay for maximizing the information encoded in the compilation considered. We find that the level of tension increases from about 3.5 σ for the f σ_{8} data compilation alone to about 6 σ when the E_{G} data are also included in the analysis. The direction of the tension is the same as implied by the f σ_{8} RSD growth data alone [lower Ω_{m} and/or weaker effective Newton constant at low redshifts for both the lensing and the growth effective Newton constants (G_{L} and G_{eff})]. These results further amplify the hints for weakening modified gravity discussed in other recent analyses.
 Publication:

Physical Review D
 Pub Date:
 March 2020
 DOI:
 10.1103/PhysRevD.101.063521
 arXiv:
 arXiv:1911.10609
 Bibcode:
 2020PhRvD.101f3521S
 Keywords:

 Astrophysics  Cosmology and Nongalactic Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 24 pages, 10 Figures. Published extended version (3 additional figures, additional less correlated dataset analysed). The data and the Mathematica data analysis files may be downloaded from http://leandros.physics.uoi.gr/egfs8plots.zip