18 février 2020Searching for alternative theories of gravitation within the Solar System

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Le 21 février 2014
De 10h30 à 12h00

Aurélien HEES

JPL, Caltech

I will briefly review the principles upon which General Relativity (GR) is built. I will also review the main effects produced by GR in the Solar System. Motivations for considering alternative theories of gravitation will be given. The main tests of GR at Solar System scales will be presented. In particular, I will present the current constraints in the two main formalisms used so far: the Parametrized Post-Newtonian formalism and the fifth force formalism. Then, some motivations for considering alternative theories of gravitation beyond the PPN and fifth force formalism will be presented. A very recent analysis of Cassini tracking data in a Modified Newtonian Dynamics formalism will be presented. After this, I will speak about a recent tool to simulate radioscience observations in very general alternative theories of gravitation. This tool computes everything (orbit of planets/spacecraft, propagation of electromagnetic signal, clock behaviour) directly from the space-time metric. As an illustration, some simulations within the Standard Model Extension and some sensitivity analyses will be presented.