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Mean of continuous variables observable {\it via} measurement on single qubit

Pawel Horodecki
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Abstract

It is shown that mean value of any observable with bounded spectrum can be uniquely determined from binary statistics of the measurement performed on {\it single} qubit ancilla coupled to a given system. The observable structure is fully encoded in the corresponding POVM. The method is generalised to the case of distant labs paradigm and discussed in the context of entanglement detection with few local measurements. The results are also discussed in the context of quantum programming.

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Pawel Horodecki. 2002-10-23. Mean of continuous variables observable {\it via} measurement on single qubit. https://doi.org/10.1103/physreva.67.060101

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