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Limits RegistryRonald Hanson's group at Delft University of Technology entangled electron spins in two diamond nitrogen-vacancy centres 1.3 km apart and violated the CHSH Bell inequality with S = 2.42 ± 0.20, closing both main loopholes at once, published in Nature in October 2015. Photonic loophole-free tests by NIST and Vienna followed months later.
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Ronald Hanson's group at Delft University of Technology entangled electron spins in two diamond nitrogen-vacancy centres 1.3 km apart and violated the CHSH Bell inequality with S = 2.42 ± 0.20, closing both main loopholes at once, published in Nature in October 2015. Photonic loophole-free tests by NIST and Vienna followed months later.
The year in which a Bell inequality violation was first demonstrated while simultaneously closing the detection (fair-sampling) and locality loopholes.
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Permanent ID limitsregistry.com/limits/LR-FIRST-LOOPHOLE-FREE-BELL-TEST
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Limits Registry. LR-FIRST-LOOPHOLE-FREE-BELL-TEST. First loophole-free Bell inequality violation. 2026.