A survey on Linear Preservers of Numerical Ranges and Radii
نویسنده
چکیده
We survey results on linear operators leaving invariant different kinds of generalized numerical ranges and numerical radii.
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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تاریخ انتشار 2001