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arXiv · 2002.05553

Perturbation of the numerical range of unitary matrices

Ryszard Kukulski·Paulina Lewandowska·Łukasz Pawela
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Abstract

In this work we show how to approach the problem of manimulating the numerical range of a unitary matrix. This task has far-reaching impact on the study of discrimination of quantum measurements. We achieve the aforementioned manipulation by introducing a method which allows us to find a unitary matrix whose numerical range contains the origin where at the same time the distance between unitary matrix and its perturbation is relative small in given metric.

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Ryszard Kukulski, Paulina Lewandowska, Łukasz Pawela. 2020-02-13. Perturbation of the numerical range of unitary matrices. https://doi.org/10.1007/978-3-030-50433-5_48

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