http://arxiv.org/abs/2305.02817
We performed a Bayesian study on the three modified gravity phenomenological parameters, the growth index $\gamma$, the dark energy equation of state parameter $w$ and the lensing deviation from the GR prediction parameter $\Sigma$, using the latest cosmological geometric, growth and lensing probes; all in a consistent implementation within the modified gravity cosmological solver code MGCLASS. We find, when we combine all our probes, i.e. CMB + BAO + $f\sigma_8$ + 3$\times$2pt clustering and lensing probes, assuming flat space, constraints still compatible with general relativity and $\Lambda$CDM with $\omega = -1.025\pm0.045$, $\gamma = 0.633\pm0.044$ and $\Sigma = 0.992\pm0.022$ at 68% level when the latter is considered as constant; and $\gamma_\ell = -0.025 \pm0.045$ when the lensing parameter is parameterized as function of the lensing index, introduced for the first time in this work, as $\Sigma(z)=\Omega_m(z)^{\gamma_\ell}$.
Z. Sakr
Fri, 5 May 23
62/67
Comments: Originally started as an invited planery talk at EREP 2022