Gravity-induced geometric spin Hall effect as a probe of universality of free fall of quantum particle

TL;DR

This paper proposes a gravity-induced geometric spin Hall effect where quantum particles experience a spin-dependent transverse shift in Earth's gravitational field, offering a potential probe for violations of the universality of free fall in quantum mechanics.

Contribution

It introduces a novel gravity-induced geometric spin Hall effect for matter waves, linking quantum spin effects to gravitational free-fall behavior.

Findings

Prediction of a spin-dependent transverse shift in quantum particles due to gravity

Potential implications for testing the universality of free fall in quantum regimes

Establishment of a new effect analogous to the geometric spin Hall effect in gravitational fields

Abstract

We present a novel fundamental effect that for the matter waves the space-averaging free-fall point of quantum particles undergoes a spin-dependent transverse shift in the gravitational field of Earth. This effect is similar to the geometric spin Hall effect (GSHE) [Aiello et al., Phys. Rev. Lett. 103, 100401 (2009)] and can be called gravity-induced GSHE. This effect suggests that there might be violations of the universality of free fall (UFF) or weak equivalence principle (WEP) in the quantum domain.