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arXiv · 2202.03368

Locally mediated entanglement in linearised quantum gravity

Marios Christodoulou·Andrea Di Biagio·Markus Aspelmeyer·Časlav Brukner·Carlo Rovelli·Richard Howl
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Abstract

The current interest in laboratory detection of entanglement mediated by gravity was sparked by an information--theoretic argument: entanglement mediated by a local field certifies that the field is not classical. Previous derivations of the effect modelled gravity as instantaneous; here we derive it from linearised quantum general relativity while keeping Lorentz invariance explicit, using the path integral formalism. In this framework, entanglement is clearly mediated by a quantum feature of the field. We also point out the possibility of observing retarded entanglement, which cannot be explained by an instantaneous interaction. This is a difficult experiment for gravity, but is plausible for the analogous electromagnetic case.

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Marios Christodoulou, Andrea Di Biagio, Markus Aspelmeyer, Časlav Brukner, Carlo Rovelli, Richard Howl. 2022-02-07. Locally mediated entanglement in linearised quantum gravity. https://doi.org/10.1103/physrevlett.130.100202

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