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arXiv · 2108.07024

The Gau-Wang-Wu conjecture on partial isometries holds in the 5-by-5 case

Ilya M. Spitkovsky·Ibrahim Suleiman·Elias Wegert
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Abstract

Gau, Wang and Wu in their LAMA'2016 paper conjectured (and proved for $n\leq 4$) that an $n$-by-$n$ partial isometry cannot have a circular numerical range with a non-zero center. We prove that this statement holds also for $n=5$.

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Ilya M. Spitkovsky, Ibrahim Suleiman, Elias Wegert. 2021-08-16. The Gau-Wang-Wu conjecture on partial isometries holds in the 5-by-5 case. https://arxiv.org/abs/2108.07024

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