Updated constraints from the Planck experiment on modified gravity

A modification of the action of the general relativity produces a different pattern for the growth of the cosmic structures below a certain length scale leaving an imprint on the cosmic microwave background anisotropies. We reexamine the upper limits on the length-scale parameter B-0 of f(R) models using the recent data from the Planck satellite experiment. We also investigate the combined constraints obtained when including the Hubble Space Telescope H-0 measurement and the baryon acoustic oscillations measurements from the SDSS, WiggleZ and BOSS surveys.