Location: Observatoire de Paris, Paris, France
PhD position in space mission ACES, Paris, France
Space mission ACES and follow-ups: beyond Standard Model and General Relativity
The ACES space mission will bring beginning of 2017 the first cold atom clock in space, PHARAO, onboard International Space Station. It aims at realizing a highly accurate and stable time scale in space. The ACES time scale will be compared to best atomic clocks on ground in more than 7 metrological labs worldwide. The altitude difference between space and ground clocks will allow to measure the gravitational redshift predicted by General Relativity with an unprecedented accuracy, as well as to search for a violation of Local Lorentz Invariance and for a possible temporal variation of the fine structure constant. Following missions are already being considered, with different types of atomic clocks and/or atom interferometers for inertial measurements.
In all these experiments, the search for a violation of fundamental principles of modern physics requires the use of a theoretical frame beyond General Relativity and Standard Model. We propose in this PhD thesis to explore one of the most exhaustive theoretical frames, recently used for treating Lorentz invariance: the Standard Model Extension (SME). A complete research program contains the following steps:
– getting familiarized with the SME model;
– modelizing ACES experiment in the SME;
– simulating observable signatures due to violations of Lorentz invariance, and estimate constraints on SME parameters;
– including a search for these terms in the (existing) ACES data analysis for obtaining constraints on the SME parameters;
– applying this work to the first ACES data expected from 2017;
– participating to the elaboration of future missions to optimize their scientific gain for fundamental physics, in particular for SME tests;
– estimating (by numerical simulation) the performances of future missions in this frame.