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  • Open Access

Gravity-induced entanglement is not a theory-independent witness of nonclassicality of the gravitational field

Andrea Di Biagio

  • Institute for Quantum Optics and Quantum Information (IQOQI) Vienna, Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna, Austria, and Basic Research Community for Physics e.V., Mariannenstraße 89, Leipzig, Germany

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Phys. Rev. D 114, 084050 – Published 19 October, 2026

DOI: https://doi.org/10.1103/r8ry-sp35

Abstract

Gravity-induced entanglement (GIE) experiments have been proposed as a theory-independent test of the quantum nature of gravity, on the strength of several no-go theorems concluding that GIE detection implies the gravitational interaction is either nonlocal or nonclassical. This is in apparent tension with a growing number of papers claiming that theories with a classical gravitational field do predict GIE. This article resolves the tension by reviewing the assumptions of the no-go theorems and highlighting the information-theoretic, rather than spatiotemporal, nature of the locality assumption. This makes violating locality not particularly problematic. Indeed, quantum electrodynamics and perturbative quantum gravity are nonlocal in the sense of the theorems. Given that GIE detection is not sufficient to rule out a classical gravitational field, the quantitative comparison of theoretical predictions in the low-energy quantum gravity regime will allow us to test whether the gravitational field is quantum or classical.

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Phys. Rev. D 114, 084050– Published 19 October, 2026
  • Received 9 July 2026
  • Accepted 1 September 2026
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