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Updated: Sep 13, 2025

Real-Time Proxy-Control of Re-Parameterized Peripheral Signals using a Close-Loop Interface
Published on: May 8, 2021
The laws of physics do not prohibit counterfactual communication
Hatim Salih1, Will McCutcheon2,3, Jonte R Hance2
1Quantum Technology Enterprise Centre, HH Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL UK.
None:
It has been conjectured that counterfactual communication is impossible, even for post-selected quantum particles. We strongly challenge this by proposing precisely such a counterfactual scheme where-unambiguously-none of Alice's photons that correctly contribute to her information about Bob's message have been to Bob. We demonstrate counterfactuality experimentally by means of weak measurements, and conceptually using consistent histories-thus simultaneously satisfying both criteria without loopholes. Importantly, the fidelity of Alice learning Bob's bit can be made arbitrarily close to unity.
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