dorsal/arxiv
View SchemaQuantum Estimation by Local Observables
| Authors | M. Hotta, M. Ozawa |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0401187 |
| URL | https://arxiv.org/abs/quant-ph/0401187 |
| DOI | 10.1103/PhysRevA.70.022327 |
| Journal | Phys. Rev. A 70, 022327 (1-13) (2004). |
Abstract
Quantum estimation theory provides optimal observations for various estimation problems for unknown parameters in the state of the system under investigation. However, the theory has been developed under the assumption that every observable is available for experimenters. Here, we generalize the theory to problems in which the experimenter can use only locally accessible observables. For such problems, we establish a Cram{\'e}r-Rao type inequality by obtaining an explicit form of the Fisher information as a reciprocal lower bound for the mean square errors of estimations by locally accessible observables. Furthermore, we explore various local quantum estimation problems for composite systems, where non-trivial combinatorics is needed for obtaining the Fisher information.
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"abstract": "Quantum estimation theory provides optimal observations for various\nestimation problems for unknown parameters in the state of the system under\ninvestigation. However, the theory has been developed under the assumption that\nevery observable is available for experimenters. Here, we generalize the theory\nto problems in which the experimenter can use only locally accessible\nobservables. For such problems, we establish a Cram{\\\u0027e}r-Rao type inequality\nby obtaining an explicit form of the Fisher information as a reciprocal lower\nbound for the mean square errors of estimations by locally accessible\nobservables. Furthermore, we explore various local quantum estimation problems\nfor composite systems, where non-trivial combinatorics is needed for obtaining\nthe Fisher information.",
"arxiv_id": "quant-ph/0401187",
"authors": [
"M. Hotta",
"M. Ozawa"
],
"categories": [
"quant-ph"
],
"doi": "10.1103/PhysRevA.70.022327",
"journal_ref": "Phys. Rev. A 70, 022327 (1-13) (2004).",
"title": "Quantum Estimation by Local Observables",
"url": "https://arxiv.org/abs/quant-ph/0401187"
},
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