EÖTVÖS, an inertial instrument for testing the Equivalence Principle Original Research Article

A really inertial platform for highest sensitivity instruments which need to be absolutely free from any disturbances like drag and other forces in space is proposed for the case of an Equivalence Principle test with differential accelerometers. A spin-stable platform, inside a co-rotating spacecraft shielding it, constitutes the reference proof mass for a simple position servo system. Position measurements, as well as signal transmissions, are made optically. Power is supplied by microwave beams. The proposed ambient-temperature EP-mission EÖTVÖS in a circular, equatorial orbit at 800 km altitude would constitute a simple, very cost-effective experiment. Limitations to the potentially very high precision (goal: one part in 1017) are expected to be set by thermal disturbances.