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On the Distinguishability of Relativistic Quantum States in Quantum Cryptography

R. Laiho·S. N. Molotkov·S. S. Nazin
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Abstract

Relativistic quantum field theory imposes additional fundamental restrictions on the distinguishability of quantum states. Because of the unavoidable delocalization of the quantum field states in the Minkowski space-time, the reliable (with unit probability) distinguishability of orthogonal states formally requires infinite time. For the cryptographic protocols which are finite in time the latter means that the effective ``noise'' is present even in the ideal communication channel because of the non-localizability of the quantum field states.

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R. Laiho, S. N. Molotkov, S. S. Nazin. 2000-06-02. On the Distinguishability of Relativistic Quantum States in Quantum Cryptography. https://arxiv.org/abs/quant-ph/0006010

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