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arXiv · 1810.10202

Searching for Signatures of Quantum Gravity in Quantum Gases

Abstract

We explore the possibility of testing the quantum nature of the gravitational field with an ensemble of ultra-cold atoms. The use of many microscopic particles may circumvent some of the experimental obstacles encountered in recent proposals involving a pair of particles with mesoscopic mass. We employ multi-parameter estimation techniques, including the quantum and classical Fisher information to provide a criteria for the observability of the quantum effects, and compare to other recently proposed schemes. Crucially, we find that by preparing the appropriate initial state, interactions mediated via a quantum-valued gravitational field provide a signature that is distinct from classical gravitational interactions. We find that a test with ultra-cold atoms would be challenging, but not implausible with moderate improvements to current experimental techniques.

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Simon A. Haine. 2019-09-13. Searching for Signatures of Quantum Gravity in Quantum Gases. https://doi.org/10.1088/1367-2630%2Fabd97d

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