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Quantum Message Disruption: A Two-State Model

Paul B. Kantor
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Abstract

A game in which one player makes unitary transformations of a simple system, and another seeks to confound the resulting state by a randomly chosen action is analyzed carefully. It is shown that the second player can reduce any system to a completely random one by rotation through an angle of 120 degrees, about an axis chosen at random. If, on the other hand, the second player is forced to behave ``classically'' by reducing the wave function, then the first play retains an advantage, which the second player may eliminate by repeated measurement using randomly selected bases.

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Paul B. Kantor. 2000-07-17. Quantum Message Disruption: A Two-State Model. https://arxiv.org/abs/quant-ph/0007054

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