Gravitational Faraday Rotation And Its Possible Test

When a mass, especially a big mass, is rotating, it will drag the local inertial frames of reference around it. This phenomenon has been called gravitomagnetism for its formal analogy with magnetism in electrodynamics. The most famous gavito- magnetic effect is the Lense-Thirring effect, and it is an important prediction of the Einstein's general relativity. But, the Lense-Thirring effect has hitherto not been detect with high accuracy. One ongoing space mission is the GPB , whose purpose is to detect the Lense-Thirring effect with an error of about 1% by measuring the precession rate of an orbiting gyroscopes.The gravitational Faraday effect is another gavitomagnetic effect. Specifically, when a linearly polarized electromagnetic wave propagates in a gravitomagnetism field, the polarization vector will rotate around the propagating direction with an angle . The gravitational Faraday rotation is very smaller and it has not been detected up to now.We have obtained that the gravitational Faraday rotation is a cumulative effect when the light is reflected in the multipass cavity. And we calculate and analyze the gravitational Faraday rotation on the surface of the Earth. If we assume that the geographical latitude of the experimental location is 45°in the north hemisphere, and the integral length is 109m, the total rotation angle of the polarization plane will be 1.4×10-13 rad. In generally, the modulation method is used to measure a small signal accurately. Therefore, we have proposed a possible experimental scheme on the Earth to test the gravitational Faraday rotation and present a reasonable experimental configuration. And we consider the influence of the Sagnac effect due to the rotation of the Earth, including how to suppress it. Finally, we analyze the feasibility of the proposed experiment scheme.