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Singlet aided infinite resource reduction in the comparison of distant fields

S. Bose·S. F. Huelga·M. B. Plenio
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Abstract

We present a task which can be faithfully solved with finite resources only when aided by particles prepared in a particular entangled state: the singlet state. The task consists of identifying the mutual parallelity or orthogonality of weak distant magnetic fields whose absolute directions are completely unknown.

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S. Bose, S. F. Huelga, M. B. Plenio. 2000-05-03. Singlet aided infinite resource reduction in the comparison of distant fields. https://doi.org/10.1103/physreva.63.032313

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