The general relativity tested in space by the MICROSCOPE satellite
MICROSCOPE is a French space mission aiming at testing the equivalence principle developed by CNES, the Observatory of Cote d’Azur and ONERA from 1999. At the foundation of the Einstein’s general relativity, the equivalence principle (EP) stipulates that all bodies are falling at the same rate in a uniform gravity field regardless of their mass or composition. Testing general relativity to its foundations is nothing more than finding the Grail of physics: the ultimate unification theory.
MICROSCOPE objective was to improve by two orders of magnitude the best current laboratory tests reaching barely 10-13. Launch in 2016, MICROSCOPE has delivered useful information for two and a half years. At the heart of the satellite, the scientific instrument developed by ONERA measured signals with a resolution better than 10-14m/s² at the particular frequency of the EP test. Apart from the scientific role, the instrument was also to feed the Drag-Free and Attitude Control System of the satellite to limit the environment accelerations to 10-13m/s² and the angular accelerations to 10-12rd/s². A first publication in 2017 confirmed at 10-14 the Einstein’s principle of equivalence with only 7% of the data available at that time. All the relevant data has been analysed and now provides the most accurate test of the equivalence principle: probably setting the test limit for the next decade.
Pending final results, the presentation will focus on the outstanding preliminary results of the MICROSCOPE mission, the first test in space of EP and will present the implications of these results for physics.