The joint essential numerical range of operators: convexity and related results
نویسندگان
چکیده
منابع مشابه
The Joint Essential Numerical Range of operators: Convexity and Related Results
LetW (A) andWe(A) be the joint numerical range and the joint essential numerical range of an m-tuple of self-adjoint operators A = (A1, . . . , Am) acting on an infinite dimensional Hilbert space, respectively. In this paper, it is shown that We(A) is always convex and admits many equivalent formulations. In particular, for any fixed i ∈ {1, . . . ,m}, We(A) can be obtained as the intersection ...
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ژورنال
عنوان ژورنال: Studia Mathematica
سال: 2009
ISSN: 0039-3223,1730-6337
DOI: 10.4064/sm194-1-6