Testing Gravitational Self-interaction via Matter-Wave Interferometry

TL;DR

This paper proposes an experimental method using matter-wave interferometry to test gravitational self-interaction effects predicted by the Schrödinger-Newton equation, potentially distinguishing it from decoherence and probing gravity's quantum nature.

Contribution

It introduces a numerical approach to assess gravitational self-interaction effects on interference fringes, offering a new experimental test for the Schrödinger-Newton model.

Findings

Gravitational self-interaction affects interference fringe width.

The effect can be distinguished from environmental decoherence.

Method provides a way to test gravity's quantization at quantum scales.

Abstract

The Schrodinger-Newton equation has frequently been studied as a nonlinear modification of the Schrodinger equation incorporating gravitational self-interaction. However, there is no evidence yet as to whether nature actually behaves this way. This work investigates a possible way to experimentally test gravitational self-interaction. The effect of self-gravity on interference of massive particles is studied by numerically solving the Schrodinger-Newton equation for a particle passing through a double-slit. The results show that the presence of gravitational self-interaction has an effect on the fringe width of the interference that can be tested in matter-wave interferometry experiments. Notably, this approach can distinguish between gravitational self-interaction and environment induced decoherence, as the latter does not affect the fringe width. This result will also provide a way to test if gravity requires to be quantized on the scale of ordinary quantum mechanics.