Abstract
The ultraprecise Gravity Probe B experiment measured the frame-dragging effect and geodetic precession on four quartz gyros. We use this result to test WEP II (weak equivalence principle II) which includes rotation in the universal free-fall motion. The free-fall Eötvös parameter for a rotating body is with a four-order improvement over previous results. The anomalous torque per unit angular momentum parameter is constrained to , , and , respectively, in the directions of geodetic effect, frame-dragging effect, and angular momentum axis; the dimensionless frequency-dependence parameter is constrained to , , and , respectively.
- Received 21 May 2011
DOI:https://doi.org/10.1103/PhysRevLett.107.051103
© 2011 American Physical Society