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arXiv · 2410.21009

State Swapping via Semiclassical Gravity

Praveer K. Gollapudi·M. Kemal Döner·André Großardt
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Abstract

The prediction of non-local phenomena is a key attribute of quantum mechanics that distinguishes it from classical theories. It was recently suggested that state swapping is one such effect that a fundamentally classical gravitational field cannot give rise to. The reasoning was that the phenomenology of classical fields is restricted to Local Operations and Classical Communication~(LOCC) whereas swapping is a non-LOCC effect, so gravity must not be a classical channel if it can give rise to such a phenomenon. Here, we show that the Hamiltonian of semiclassical gravity results in an evolution of coherent states that is virtually indistinguishable from swapping them, both theoretically and experimentally. Our results indicate that drawing a definitive conclusion about the nature of gravity based solely on its ability to swap a pair of coherent states would be premature. We discuss the implications of these results regarding proposed experimental tests for the quantum nature of gravity and clarify some conceptual issues.

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Praveer K. Gollapudi, M. Kemal Döner, André Großardt. 2024-10-28. State Swapping via Semiclassical Gravity. https://doi.org/10.1103/physreva.111.012208

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