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Limits RegistryThe French CNES/ONERA satellite MICROSCOPE compared the free fall of titanium and platinum test masses in orbit from 2016 to 2018. Its final result, η = [-1.5 ± 2.3 (stat) ± 1.5 (syst)]x10^-15 published in Physical Review Letters in September 2022, found no violation of Einstein's equivalence principle at about the 10^-15 level, roughly a hundred times better than torsion-balance tests on Earth.
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The French CNES/ONERA satellite MICROSCOPE compared the free fall of titanium and platinum test masses in orbit from 2016 to 2018. Its final result, η = [-1.5 ± 2.3 (stat) ± 1.5 (syst)]x10^-15 published in Physical Review Letters in September 2022, found no violation of Einstein's equivalence principle at about the 10^-15 level, roughly a hundred times better than torsion-balance tests on Earth.
The smallest uncertainty achieved on the Eötvös ratio η, the fractional difference in free-fall acceleration between two bodies of different composition.
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Limits Registry. LR-EQUIVALENCE-PRINCIPLE-TEST-PRECISION. Most precise test of the weak equivalence principle. 2026.