Numerical Ranges of C 0(N) Contractions
نویسندگان
چکیده
منابع مشابه
Multiplicative Preservers of C-Numerical Ranges and Radii
Multiplicative preservers of C-numerical ranges and radii on certain groups and semigroups of complex n × n matrices are characterized. The general and special linear groups are considered, as well as the semigroups of matrices having ranks not exceeding k, with k fixed in advance. For a fixed C, it turns out that typically the multiplicative preservers of the C-numerical range (or radius) have...
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ژورنال
عنوان ژورنال: Integral Equations and Operator Theory
سال: 2010
ISSN: 0378-620X,1420-8989
DOI: 10.1007/s00020-010-1849-9