Table 4 Compilation of UFF/WEP tests. Numbers in brackets are results expected in the near future, and we also show the performance of an STE-QUEST-like atom-interferometry mission in the context of this road-map. Further information about this road-map milestone is provided in Sect. 8. In addition, lunar laser ranging probes the UFF at a level \(\sim 2 \times 10^{-14}\) for the Earth and Moon [224]
From: Cold atoms in space: community workshop summary and proposed road-map
Class | Elements | η | Year [ref] | Comments |
|---|---|---|---|---|
Classical | Be–Ti | 2 × 10−13 | 2008 [220] | Torsion balance |
Pt–Ti | 1 × 10−14 | 2017 [193] | MICROSCOPE first results | |
Pt–Ti | (10−15) | 2019+ | MICROSCOPE full data | |
Hybrid | 133Cs–CC | 7 × 10−9 | 2001 [225] | Atom interferometry and |
87Rb–CC | 7 × 10−9 | 2010 [226] | macroscopic corner cube | |
Quantum | 39K–87Rb | 5 × 10−7 | 2014 [227] | different elements |
87Sr–88Sr | 2 × 10−7 | 2014 [228] | same element, fermion vs. boson | |
85Rb–87Rb | 3 × 10−8 | 2015 [229] | same element, different isotopes | |
85Rb–87Rb | 3.8 × 10−12 | 2020 [230] | ≥ 10 m towers | |
85Rb–87Rb | (10−13) | 2020+ [200] | ||
170Yb–87Rb | (10−13) | 2020+ [231] | ||
41K–87Rb | 10−17 | 2035+ | STE-QUEST-like mission | |
Antimatter | H̅–H | (10−2) | 2020+ [232] | under construction at CERN |