Proposals for precision experimental tests of the equivalence principle under terrestrial conditions with magnetically suspended test bodies

Precision experimental test of the equivalence principle with a terrestrial device that employs magnetically suspended heavy (several ten kilograms) test bodies are described. The magnetic field used in this device is created by two electromagnets rotating in opposite directions at equal speeds. The coils of the two electromagnets re connected in series to the same source and have opposite polarities. Since test bodies suspended in such a device form an oscillating system with a vanishingly small torsional rigidity, the apparatus is highly sensitive to the small forces under investigation. The technique of measurement is based on such physical phenomena as antiresonance, dynamical damping of background oscillations, and vibrational displacement of test bodies under an oscillatory force. It is expected that the use of such a device in a terrestrial laboratory will make it possible either to verify the equivalence principle to a significantly improved precision of ∼10-15 or to reveal its violation. The experiment may be sensitive to the effects of weak interaction