Operator norms determined by their numerical ranges
نویسندگان
چکیده
منابع مشابه
Induced Norms, States, and Numerical Ranges
It is shown that two induced norms are the same if and only if the corresponding norm numerical ranges or radii are the same, which in turn is equivalent to the vector states and mixed states arising from the norms being the same. The proofs depend on an auxiliary result of independent interest which concerns when two closed convex sets in a topological vector space are multiples of each other.
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ژورنال
عنوان ژورنال: Proceedings of the Edinburgh Mathematical Society
سال: 1971
ISSN: 0013-0915,1464-3839
DOI: 10.1017/s0013091500026973