Dark $R^2$ at low energy

International audienceWe consider the consequences of the leading quartic corrections to the Einstein–Hilbert action of gravity at low energy. Using the equivalence between the scalar R2 contribution and a scalar-tensor field theory, we analyze the possible ways of detecting the associated scalaron and suggest that short distance tests of gravity, and in particular future tests of Newton’s law aboard satellites, would provide the best environment to detect such a modification of gravity. We also analyze the regimes for which the R2 theory would result as a low energy manifestation of putative high energy UV completions involving extra dimensions. In the four-dimensional N = 1 supergravity limit of such extra-dimensional models, the R2 models would emerge from the stabilization of a nearly no-scale superfield such as the ones associated to the Kähler modulus corresponding to the breathing mode of a six-dimensional compactification