Angular momentum effects in Michelson-Morley type experiments

TL;DR

This paper investigates how the angular momentum density of a gravitational source influences light travel times in interferometers, revealing effects that could impact gravitational wave detection sensitivity.

Contribution

It provides a detailed analysis of angular momentum effects on light propagation in stationary, axisymmetric spacetimes without approximating the metric, including Earth's weak field case.

Findings

Angular momentum density affects light travel times in interferometers.

Effects are comparable to gravitational wave detector sensitivities for non-geodesic paths.

The effect is negligible for free, geodesic light rays.

Abstract

The effect of the angular momentum density of a gravitational source on the times of flight of light rays in an interferometer is analyzed. The calculation is made imagining that the interferometer is at the equator of the gravity source and, as long as possible, the metric, provided it is stationary and axisymmetric, is not approximated. Finally, in order to evaluate the size of the effect in the case of the Earth a weak field approximation is introduced. For laboratory scales and non-geodesic paths the correction turns out to be comparable with the sensitivity expected in gravitational waves interferometric detectors, whereas it drops under the threshold of detectability when using free (geodesic) light rays.