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arXiv · 1012.2130

Group theoretic structures in the estimation of an unknown unitary transformation

G. Chiribella
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Abstract

This paper presents a series of general results about the optimal estimation of physical transformations in a given symmetry group. In particular, it is shown how the different symmetries of the problem determine different properties of the optimal estimation strategy. The paper also contains a discussion about the role of entanglement between the representation and multiplicity spaces and about the optimality of square-root measurements.

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G. Chiribella. 2011-01-24. Group theoretic structures in the estimation of an unknown unitary transformation. https://doi.org/10.1088/1742-6596%2F284%2F1%2F012001

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