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arXiv · 2211.02623

Efficiently computing the Uhlmann fidelity for density matrices

Andrew J. Baldwin·Jonathan A. Jones
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Abstract

We consider the problem of efficiently computing the Uhlmann fidelity in the case when explicit density matrix descriptions are available. We derive an alternative formula which is simpler to evaluate numerically, saving a factor of 10 in time for large matrices.

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Andrew J. Baldwin, Jonathan A. Jones. 2022-11-04. Efficiently computing the Uhlmann fidelity for density matrices. https://doi.org/10.1103/physreva.107.012427

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