6533b7dcfe1ef96bd1272b3d

RESEARCH PRODUCT

Current status of modified gravity

subject

description

We revisit the cosmological viability of the Hu-Sawicki modified gravity scenario. The impact of such a modification on the different cosmological observables, including gravitational waves, is carefully described. The most recent cosmological data, as well as constraints on the relationship between the clustering parameter ${\ensuremath{\sigma}}_{8}$ and the current matter mass-energy density ${\mathrm{\ensuremath{\Omega}}}_{m}$ from cluster number counts and weak lensing tomography, are considered in our numerical calculations. The strongest bound we find is $|{f}_{R0}|l3.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ at 95% C.L. Forthcoming cluster surveys covering $10\text{ }000\text{ }\text{ }{\mathrm{deg}}^{2}$ in the sky, with galaxy surface densities of $\mathcal{O}(10)\text{ }\text{ }{\mathrm{arcmin}}^{\ensuremath{-}2}$ could improve the precision in the ${\ensuremath{\sigma}}_{8}$-${\mathrm{\ensuremath{\Omega}}}_{m}$ relationship, tightening the above constraint.