The joint numerical range of commuting matrices
نویسندگان
چکیده
It is shown that for $n \le 3$ the joint numerical range of a family commuting $n\times n$ complex matrices always convex; \ge 4$ there are two whose not convex.
منابع مشابه
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ژورنال
عنوان ژورنال: Studia Mathematica
سال: 2022
ISSN: ['0039-3223', '1730-6337']
DOI: https://doi.org/10.4064/sm200622-31-5