May 16, 2022
Testing gravity in space : The MICROSCOPE mission and the equivalence principle
Joel Bergé (ONERA)
Description :

The MICROSCOPE mission allowed for an unprecedented precision on the test of the Weak Equivalence Principle (WEP). The WEP states that all bodies fall at the same rate, independently of their mass and composition, and is the cornerstone of General Relativity (GR). MICROSCOPE’s measurement concept relied on comparing the free fall of two test masses of different compositions as they orbited the Earth.

Beside testing GR’s foundation, it allowed us to shed light on modified gravity models involving the existence of a putative fifth force. For instance, the test of the equivalence principle in the Earth orbit sets constraints on long-range (of order a thousand kilometres and more) fifth force, while the interaction of MICROSCOPE’s test masses with each other provides clues on a shorter (of order 0.1 m) fifth force.

In this talk, I will first present the MICROSCOPE experiment and test of the WEP. I will then discuss how MICROSCOPE could set new constraints on fifth force models such as a Yukawa deviation from Newtonian gravity, a light dilaton and a chameleon field.


2007 : thèse au CEA Saclay, “Les lentilles gravitationnelles faibles vers la cosmologie de haute précision”, sous la direction d’Alexandre Réfrégier
2008 – 2011 : postdoc au JPL et Caltech sur le weak lensing (phénoménologie et analyse de données)
2011 – 2012 : postdoc à l’ETH Zurich sur le weak lensing (analyse de données, simulations, Euclid)

2013 – présent : ingénieur-chercheur à l’ONERA (DPHY -- Département de Physique, Instrumentation, Environnement, Espace). Travail sur MICROSCOPE (segment sol et analyse de données) et concepts de tests de la gravitation dans l’espace.



Monday, May 16, 2022 at 2:00:00 PM Central European Summer Time
Monday, May 16, 2022 at 3:00:00 PM Central European Summer Time
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