Probing the nonclassical dynamics of a quantum particle in a gravitational field

TL;DR

This paper proposes an experimental approach to test nonclassical effects in the quantum dynamics of particles under gravity, potentially revealing deviations from the Schrödinger equation in accessible regimes.

Contribution

It introduces a novel interferometric setup to detect gravitational effects on quantum particles, aiming to observe deviations from standard quantum mechanics.

Findings

Potential to detect deviations from Schrödinger dynamics due to gravity

Experimental parameters within current technological capabilities

Provides a direct test of nonclassical behavior in gravitational fields

Abstract

In quantum mechanics, the time evolution of particles is given by the Schr\"odinger equation. It is valid in a nonrelativistic regime where the interactions with the particle can be modelled by a potential and quantised fields are not required. This has been verified in countless experiments when the interaction is of electromagnetic origin, but also corrections due to the quantised field are readily observed. When the interaction is due to gravity, then one cannot expect to see effects of the quantised field in current-technology Earth-bound experiments. However, this does not yet guarantee that in the accessible regime, the time evolution is accurately given by the Schr\"odinger equation. Here we propose to measure the effects of an asymmetric mass configuration on a quantum particle in an interferometer. For this setup we show that with parameters within experimental reach, one can be sensitive to possible deviations from the Schr\"odinger equation, beyond the already verified lowest-order regime. Performing this experiment will hence directly test the nonclassical behaviour of a quantum particle in the gravitational field.