Tension of the $E_G$ statistic and RSD data with Planck/$\Lambda$CDM and
  implications for weakening gravity
  The $E_G$ statistic is a powerful probe for detecting deviations from GR by
combining weak lensing (WL), real-space 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 up to date
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 up to
date compilation of $f\sigma_8$ data from RSD observations to identify the
current level of tension between the Planck/$\Lambda$CDM standard model based
on general relativity and a general model independent redshift evolution
parametrization of $G_L$ and $G_{eff}$. Each $f\sigma_8$ datapoint considered
has been published separately in the context of independent analyses of
distinct galaxy samples. However, there are correlations among the datapoints
considered due to overlap of the analyzed galaxy samples. Due to these
correlations the derived levels of tension of the best fit parameters with
Planck/$\Lambda$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 $3.5\sigma$ for the $f\sigma_8$ data
compilation alone to about $6\sigma$ when the $E_G$ data are also included in
the analysis. The direction of the tension is the same as implied by the
$f\sigma_8$ RSD growth data alone (lower $\Omega_m$ 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.
