Quantum cryptography as a retrodiction problem.
We propose a quantum key distribution protocol based on a quantum retrodiction protocol, known as the Mean King problem. The protocol uses a two way quantum channel. We show security against coherent attacks in a transmission-error free scenario, even if Eve is allowed to attack both transmissions. This establishes a connection between retrodiction and key distribution.
Werner
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Institut für Theoretische Physik, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover. albert.werner@itp.uni-hannover.de
Franz
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Werner
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