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arXiv · 2607.07913

A majorization relation for a sum of two tensor products of positive semidefinite operators

Mohammad A. Alhejji·Cole Kelson-Packer
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Abstract

We use linear programming to prove a separable version of Ky Fan's majorization relation for a sum of two operators that are each a tensor product of $n$ positive semidefinite operators. We give an example showing that such a relation does not hold in general for sums of three or more tensor products of three or more positive semidefinite operators.

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Mohammad A. Alhejji, Cole Kelson-Packer. 2026-07-08. A majorization relation for a sum of two tensor products of positive semidefinite operators. https://arxiv.org/abs/2607.07913

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