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arXiv · 0811.1209

Localized closed timelike curves can perfectly distinguish quantum states

Todd A. Brun·Jim Harrington·Mark M. Wilde
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Abstract

We show that qubits traveling along closed timelike curves are a resource that a party can exploit to distinguish perfectly any set of quantum states. As a result, an adversary with access to closed timelike curves can break any prepare-and-measure quantum key distribution protocol. Our result also implies that a party with access to closed timelike curves can violate the Holevo bound.

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Todd A. Brun, Jim Harrington, Mark M. Wilde. 2008-11-07. Localized closed timelike curves can perfectly distinguish quantum states. https://doi.org/10.1103/physrevlett.102.210402

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