TY - JOUR
T1 - Space test of the equivalence principle
T2 - First results of the MICROSCOPE mission
AU - Touboul, Pierre
AU - Métris, Gilles
AU - Cipolla, Valerio
AU - Damour, Thibault
AU - Danto, Pascale
AU - Guidotti, Pierre Yves
AU - Hardy, Emilie
AU - Robert, Alain
AU - Visser, Pieter
AU - More Authors, null
PY - 2019/10/18
Y1 - 2019/10/18
N2 - The weak equivalence principle (WEP), stating that two bodies of different compositions and/or mass fall at the same rate in a gravitational field (universality of free fall), is at the very foundation of general relativity. The MICROSCOPE mission aims to test its validity to a precision of 10-15, two orders of magnitude better than current on-ground tests, by using two masses of different compositions (titanium and platinum alloys) on a quasi-circular trajectory around the Earth. This is realised by measuring the accelerations inferred from the forces required to maintain the two masses exactly in the same orbit. Any significant difference between the measured accelerations, occurring at a defined frequency, would correspond to the detection of a violation of the WEP, or to the discovery of a tiny new type of force added to gravity. MICROSCOPE's first results show no hint for such a difference, expressed in terms of Eötvös parameter (both 1 uncertainties) for a titanium and platinum pair of materials. This result was obtained on a session with 120 orbital revolutions representing 7% of the current available data acquired during the whole mission. The quadratic combination of 1 uncertainties leads to a current limit on of about.
AB - The weak equivalence principle (WEP), stating that two bodies of different compositions and/or mass fall at the same rate in a gravitational field (universality of free fall), is at the very foundation of general relativity. The MICROSCOPE mission aims to test its validity to a precision of 10-15, two orders of magnitude better than current on-ground tests, by using two masses of different compositions (titanium and platinum alloys) on a quasi-circular trajectory around the Earth. This is realised by measuring the accelerations inferred from the forces required to maintain the two masses exactly in the same orbit. Any significant difference between the measured accelerations, occurring at a defined frequency, would correspond to the detection of a violation of the WEP, or to the discovery of a tiny new type of force added to gravity. MICROSCOPE's first results show no hint for such a difference, expressed in terms of Eötvös parameter (both 1 uncertainties) for a titanium and platinum pair of materials. This result was obtained on a session with 120 orbital revolutions representing 7% of the current available data acquired during the whole mission. The quadratic combination of 1 uncertainties leads to a current limit on of about.
KW - drag-free
KW - equivalence principle
KW - experimental gravitation
KW - general relativity
KW - microsatellite
KW - MICROSCOPE
KW - space accelerometers
UR - http://www.scopus.com/inward/record.url?scp=85075605603&partnerID=8YFLogxK
U2 - 10.1088/1361-6382/ab4707
DO - 10.1088/1361-6382/ab4707
M3 - Article
AN - SCOPUS:85075605603
SN - 0264-9381
VL - 36
JO - Classical and Quantum Gravity
JF - Classical and Quantum Gravity
IS - 22
M1 - 225006
ER -