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Existing experiments suffice to indirectly verify the quantum essence of gravity

Martin Plávala

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Phys. Rev. D 113, 085004 – Published 2 April, 2026

DOI: https://doi.org/10.1103/87dc-qt73

Abstract

The gravity-mediated entanglement experiments employ concepts from quantum information to argue that if entanglement due to gravitational interaction is observed, then gravity cannot be described by a classical system. However, the proposed experiments remain beyond our current technological capability, with optimistic projections placing the experiment outside of the short-term future. Here we argue that current matter-wave interferometers are sufficient to indirectly prove that gravitational interaction creates entanglement between two systems. Specifically, we prove that if we experimentally verify the Schrödinger equation for a single delocalized system interacting gravitationally with an external mass, then, under one of two reasonable assumptions, the time evolution of two delocalized systems will lead to gravity-mediated entanglement.

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Corrections

11 September, 2026

Correction: A typographical error in the first sentence of the fourth paragraph of Sec. IV B has been fixed.

Article Text

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Outline

Information

Phys. Rev. D 113, 085004– Published 2 April, 2026
  • Received 11 August 2025
  • Revised 15 December 2025
  • Accepted 16 March 2026
  • Corrected 11 September 2026
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