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Updated: Jul 3, 2026

Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
Spacelike separation in a Bell test assuming gravitationally induced collapses
D Salart1, A Baas, J A W van Houwelingen
1Group of Applied Physics, University of Geneva, 20, Rue de l'Ecole de Médecine, CH-1211 Geneva 4, Switzerland.
Abstract:
We report on a Bell experiment with spacelike separation assuming that the measurement time is related to gravity-induced state reduction. Two energy-time entangled photons are sent through optical fibers and directed into unbalanced interferometers at two receiving stations separated by 18 km. At each station, the detection of a photon triggers the displacement of a macroscopic mass. The timing ensures spacelike separation from the moment a photon enters its interferometer until the mass has moved. Two-photon interference fringes with a visibility of up to 90.5% are obtained, leading to a violation of the Bell inequality.
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