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Asymptotic quantum cloning is state estimation

Joonwoo Bae·Antonio Acin
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Abstract

The impossibility of perfect cloning and state estimation are two fundamental results in Quantum Mechanics. It has been conjectured that quantum cloning becomes equivalent to state estimation in the asymptotic regime where the number of clones tends to infinity. We prove this conjecture using two known results of Quantum Information Theory: the monogamy of quantum correlations and the properties of entanglement breaking channels.

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Joonwoo Bae, Antonio Acin. 2006-03-09. Asymptotic quantum cloning is state estimation. https://doi.org/10.1103/physrevlett.97.030402

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