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arXiv · 1109.5661

Quantum measurement bounds beyond the uncertainty relations

Vittorio Giovannetti·Seth Lloyd·Lorenzo Maccone
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Abstract

We give a bound to the precision in the estimation of a parameter in terms of the expectation value of an observable. It is an extension of the Cramer-Rao inequality and of the Heisenberg uncertainty relation, where the estimation precision is typically bounded in terms of the variance of an observable.

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Vittorio Giovannetti, Seth Lloyd, Lorenzo Maccone. 2011-09-26. Quantum measurement bounds beyond the uncertainty relations. https://doi.org/10.1103/physrevlett.108.260405

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