New bounds on dark energy induced fifth forces.

We consider the gravitational Wilsonian effective action at low energy when all the particles of the standard model have decoupled. When the R² terms dominate, the theory is equivalent to a scalar-tensor theory with the universal coupling β=1/√6 to matter for which we present strong lower and upper bounds on the scalaron mass m obtained by using results from the Eöt-Wash experiment on the modification of the inverse-square law, the observations of the hot gas of galaxy clusters, and the Planck satellite data on the neutrino masses. In terms of the range of the scalar interaction mediated over a distance of order m-1, this leads to the small interval 4μm≲m-1≲68μm within reach of future experimental tests of deviations from Newton's gravitational inverse-square law. [ABSTRACT FROM AUTHOR]