Phenomenological constraints on the Kehagias-Sfetsos solution in the Horava-Lifshitz gravity from solar system orbital motions

TL;DR

This paper investigates the effects of the Kehagias-Sfetsos solution in Horava-Lifshitz gravity on planetary orbits, deriving constraints on the theory's parameters from solar system observations, and finds it cannot explain the Pioneer anomaly.

Contribution

It analytically derives the perihelion precession induced by the Kehagias-Sfetsos solution and constrains the HL parameter using planetary data, a novel approach in testing HL gravity.

Findings

Lower bounds on HL parameter  of order 10^-12 to 10^-24 from planetary precessions.

The solution cannot account for the Pioneer anomaly at distances greater than 20 AU.

Planetary data provide stringent constraints on HL gravity parameters.

Abstract

We focus on Horava-Lifshitz (HL) theory of gravity, and, in particular, on the Kehagias and Sfetsos s solution that is the analog of Schwarzschild black hole of General Relativity. In the weak-field and slow-motion approximation we analytically work out the secular precession of the longitude of the pericentre of a test particle induced by this solution. Its analytical form is different from that of the general relativistic Einstein's pericentre precession. Then, we compare it to the latest determinations of the corrections to the standard Newtonian/ Einsteinian planetary perihelion precessions recently estimated by E.V. Pitjeva with the EPM2008 ephemerides. It turns out that the planets of the solar system, taken singularly one at a time, allow to put lower bounds on the adimensional HL parameter \psi_0 of the order of 10^-12 (Mercury) 10^-24 (Pluto). They are not able to account for the Pioneer anomalous acceleration for r > 20 AU.