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arXiv · 2002.02898

One from many: Estimating a function of many parameters

Jonathan A. Gross·Carlton M. Caves
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Abstract

Difficult it is to formulate achievable sensitivity bounds for quantum multiparameter estimation. Consider a special case, one parameter from many: many parameters of a process are unknown; estimate a specific linear combination of these parameters without having the ability to control any of the parameters. Superficially similar to single-parameter estimation, the problem retains genuinely multiparameter aspects. Geometric reasoning demonstrates the conditions, necessary and sufficient, for saturating the fundamental and attainable quantum-process bound in this context.

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Jonathan A. Gross, Carlton M. Caves. 2020-02-07. One from many: Estimating a function of many parameters. https://doi.org/10.1088/1751-8121%2Fabb9ed

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