An exact correspondence between the quantum Fisher information and the Bures metric

Sisi Zhou; Liang Jiang

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arXiv · 1910.08473

An exact correspondence between the quantum Fisher information and the Bures metric

Sisi Zhou·Liang Jiang

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Abstract

The quantum information and the Bures metric are equivalent to each other, except at points where the rank of the density matrix changes. Here we show that by slightly modifying the definition of the Bures metric, the quantum information will be fully equivalent to the Bures metric without exception.

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Sisi Zhou, Liang Jiang. 2019-10-18. An exact correspondence between the quantum Fisher information and the Bures metric. https://arxiv.org/abs/1910.08473

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