Self-gravitating Interferometry and Intrinsic Decoherence

TL;DR

This paper develops a self-gravitating interferometer model within canonical quantum gravity to explore whether intrinsic gravitational decoherence limits quantum coherence due to general relativistic effects.

Contribution

It introduces a spherical symmetric, shell-based interferometer model with internal beam optics, enabling analysis of gravitational decoherence effects in quantum gravity.

Findings

Coherence can be maintained despite general relativistic effects under certain conditions

The model demonstrates how beam-splitting and reflection can be encoded in shell dynamics

Implications for the fundamental limits of quantum coherence due to gravity

Abstract

To investigate the possibility that intrinsic gravitational decoherence can be theoretically demonstrated within canonical quantum gravity, we develop a model of a self-gravitating interferometer. We search for evidence in the resulting interference pattern that would indicate coherence is fundamentally limited due to general relativistic effects. To eliminate the occurence of gravitational waves, we work in spherical symmetry, and construct the "beam" of the interferometer out of WKB states for an infinitesimally thin shell of matter. For internal consistency, we encode information about the beam optics within the dynamics of the shell itself, by arranging an ideal fluid on the surface of the shell with an equation of state that enforces beam-splitting and reflections. We then determine sufficient conditions for (interferometric) coherence to be fully present even after general relativistic corrections are introduced, test whether or not they can be satisfied, and remark on the implications of the results.