The rotation of polarization by gravitational waves

Abstract

There are conflicting statements in the literature about the gravitational Faraday rotation of the plane of polarization of polarized electromagnetic radiation travelling through a gravitational wave. This issue is reconsidered using a simple formalism describing the rotation of the plane of polarization in a gravitational field, in the geometric optics approximation. It is shown that, to first order in the gravitational wave amplitude, the rotation angle is a boundary effect which vanishes for localized (astrophysically generated) gravitational waves and is non-zero, but nevertheless negligible, for cosmological gravitational waves.