Bounding quantum gravity inspired decoherence using atom interferometry

TL;DR

This paper uses recent atom interferometry experiments to place stringent bounds on quantum gravity-induced decoherence, effectively ruling out certain collapse models at large scales.

Contribution

It provides experimental constraints on quantum gravity inspired collapse models using high-precision atom interferometry data.

Findings

Quantum gravity induced decoherence is strongly bounded by recent experiments.

The data rules out the specific collapse model proposed by Ellis et al. in the parameter regime considered.

Atom interferometry can effectively test and constrain theories of quantum gravity related decoherence.

Abstract

Hypothetical models have been proposed in which explicit collapse mechanisms prevent the superposition principle to hold at large scales. In particular, the model introduced by Ellis and co-workers [Phys. Lett. B ${\bf 221}$, 113 (1989)] suggests that quantum gravity might be responsible for the collapse of the wavefunction of massive objects in spatial superpositions. We here consider a recent experiment reporting on interferometry with atoms delocalized over half a meter for timescale of a second [Nature ${\bf 528}$, 530 (2015)] and show that the corresponding data strongly bound quantum gravity induced decoherence and rule it out in the parameter regime considered originally.