Exploring the Foundations of the Physical Universe with Space Tests of the Equivalence Principle

Baptiste Battelier (1) , Joël Bergé (2) , Andrea Bertoldi (1) , Luc Blanchet (3) , Kai Bongs (4) , Philippe Bouyer (1) , Claus Braxmaier (5, 6) , Davide Calonico (7) , Pierre Fayet (8, 9) , Naceur Gaaloul (10) , Christine Guerlin (11) , Aurelien Hees (12) , Philippe Jetzer (13) , Claus Lämmerzahl (6) , Steve Lecomte (14) , Christophe Le Poncin-Lafitte (12) , S. Loriani (10) , Gilles Métris (15) , M. Nofrarias (16, 17) , Ernst Rasel (10) , Serge Reynaud (11) , Manuel Rodrigues (2) , Markus Rothacher (18) , Albert Roura (19) , Christophe Salomon (11) , Stephan Schiller (20) , Wolfgang P. Schleich (19) , C. Schubert (10) , Carlos Sopuerta (16, 17) , Fiodor Sorrentino (21) , Tim J. Sumner (22) , Guglielmo M. Tino (23, 24) , Philip Tuckey (12) , Wolf von Klitzing (25) , Lisa Wörner (5, 6) , Peter Wolf (12) , Martin Zelan (26)

1 LP2N - Laboratoire Photonique, Numérique et Nanosciences
2 DPHY, ONERA, Université Paris Saclay [Châtillon]
3 IAP - Institut d'Astrophysique de Paris
4 School of Physics and Astronomy [Birmingham]
5 DLR - Deutsches Zentrum für Luft- und Raumfahrt
6 ZARM - Center of Applied Space Technology and Microgravity
7 INRiM - Istituto Nazionale di Ricerca Metrologica
8 Champs, Gravitation et Cordes
9 CPHT - Centre de Physique Théorique [Palaiseau]
10 QUEST - Centre for Quantum Engineering and Space-time Research
11 LKB (Jussieu) - Laboratoire Kastler Brossel
12 SYRTE - Systèmes de Référence Temps Espace
13 Physik-Institut [Zürich]
14 CSEM - Centre Suisse d'Electronique et Microtechnique SA
15 GEOAZUR 7329 - Géoazur
16 ICE-CSIC - Institute of Space Sciences [Barcelona]
17 IEEC-CSIC - Institute for Space Studies of Catalonia [Barcelona]
18 IGP - Institute of Geodesy and Photogrammetry [Zürich]
19 DLR - German Aerospace Center
20 Institut fur Experimentalphysik
21 INFN, Sezione di Genova - Istituto Nazionale di Fisica Nucleare, Sezione di Genova
22 Imperial College London
23 LENS - European Laboratory for Non-Linear Spectroscopy
24 INFN, Sezione di Firenze - Istituto Nazionale di Fisica Nucleare, Sezione di Firenze
25 FORTH-IESL - Institute of Electronic Structure and Laser
26 RISE Research Institutes of Sweden

We present the scientific motivation for future space tests of the equivalence principle, and in particular the universality of free fall, at the 10− 17 level or better. Two possible mission scenarios, one based on quantum technologies, the other on electrostatic accelerometers, that could reach that goal are briefly discussed. This publication is a White Paper written in the context of the Voyage 2050 ESA Call for White Papers.

Keywords: Equivalence principle; Gravitation; Satellite

Domains: Physics [physics]; Astrophysics [astro-ph]

Baptiste Battelier, Joël Bergé, Andrea Bertoldi, Luc Blanchet, Kai Bongs, et al.. Exploring the Foundations of the Physical Universe with Space Tests of the Equivalence Principle. Experimental Astronomy, 2021, Voyage 2050 – science themes for ESA’s long-term plan for the Scientific Programme: the nearby and distant Universe, 51 (3), pp.1695-1736. ⟨10.1007/s10686-021-09718-8⟩. ⟨hal-02418020v3⟩