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arXiv · 1710.08695

When Cavendish meets Feynman: A quantum torsion balance for testing the quantumness of gravity

Matteo Carlesso·Mauro Paternostro·Hendrik Ulbricht·Angelo Bassi
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Abstract

We propose a thought experiment, based on a mechanism that is reminiscent of Cavendish's torsion balance, to investigate the possible quantum nature of the gravitational field generated by the quantum superposition state of a massive system. Our proposal makes use of the dynamics of a ultra-stable optically levitated nanomechanical rotor endowed with a spin to generate a quantum angular superposition that is then tested through standard Ramsey-like scheme. Gravity manifests itself as an effective decoherence mechanism, whose strength is different-and, as we show, appreciable-in the classical and quantum case. By incorporating both the source for decoherence and the mechanism to probe it, the experiment that we propose allows for a much reduced degree of control and dynamical engineering.

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Matteo Carlesso, Mauro Paternostro, Hendrik Ulbricht, Angelo Bassi. 2017-10-24. When Cavendish meets Feynman: A quantum torsion balance for testing the quantumness of gravity. https://arxiv.org/abs/1710.08695

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