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arXiv · 2607.27116

Ky Fan majorization for binary tensor products

Michael M. Wolf·Yuanheng Zhou
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Abstract

We provide a short proof of a Ky Fan-type majorization relation for the singular values of a sum of binary tensor products of matrices. This generalizes Alhejji's result (arXiv:2410.18254) from two summands to arbitrary sums and from positive matrices to arbitrary matrices. As an application, we show a majorization relation between the singular values of a completely positive map and those of its Kraus operators.

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Michael M. Wolf, Yuanheng Zhou. 2026-07-29. Ky Fan majorization for binary tensor products. https://arxiv.org/abs/2607.27116

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