Quantum effects in rotating reference frames

TL;DR

This paper proposes a quantum optical experiment using Hong-Ou-Mandel interference to observe Kerr frame-dragging effects, demonstrating how quantum effects can reveal gravitational phenomena in rotating spacetime.

Contribution

It introduces a novel quantum optical method to detect frame-dragging effects via photon interference, bridging quantum optics and general relativity.

Findings

Quantum interference reveals Kerr frame-dragging effects.

Feasibility of experiment using optical fibers with minimal dispersion.

Direction-dependent group velocity differences enable observation.

Abstract

We consider the time delay of interfering single photons oppositely traveling in the Kerr metric of a rotating massive object. Classically, the time delay shows up as a phase difference between coherent sources of light. In quantum mechanics, the loss in visibility due to the indistinguishability of interfering photons is directly related to the time delay. We can thus observe the Kerr frame-dragging effect using the Hong-Ou-Mandel (HOM) dip, a purely quantum mechanical effect. By Einstein's equivalence principle, we can analogously consider a rotating turntable to simulate the Kerr metric. We look at the feasibility of such an experiment using optical fibre, and note a cancellation in the second-order dispersion but a direction-dependent difference in group velocity. However, for the chosen experimental parameters, we can effectively assume light propagating through a vacuum.