Horava-Lifshitz gravity: tighter constraints for the Kehagias-Sfetsos solution from new solar system data
Abstract
We analytically work out the perturbation induced by the Kehagias-Sfetsos (KS) space-time solution of the Horava-Lifshitz (HL) modified gravity at long distances on the two-body range for a pair of test particles A and B orbiting the same mass M. We apply our results to the most recently obtained range-residuals δ for some planets of the solar system (Mercury, Mars, Saturn) ranged from the Earth to effectively constrain the dimensionsless KS parameter 0 for the Sun. We obtain 0 >= 7.2 x 10-10 (Mercury), 0 >= 9 x 10-12 (Mars), 0 >= 1.7 x 10-12 (Saturn). Such lower bounds are tighter than other ones existing in literature by several orders of magnitude. We also preliminarily obtain 0 >= 8 x 10-10 for the system constituted by the S2 star orbiting the Supermassive Black Hole (SBH) in the center of the Galaxy.