Essential numerical range of elementary operators
نویسندگان
چکیده
منابع مشابه
On the decomposable numerical range of operators
Let $V$ be an $n$-dimensional complex inner product space. Suppose $H$ is a subgroup of the symmetric group of degree $m$, and $chi :Hrightarrow mathbb{C} $ is an irreducible character (not necessarily linear). Denote by $V_{chi}(H)$ the symmetry class of tensors associated with $H$ and $chi$. Let $K(T)in (V_{chi}(H))$ be the operator induced by $Tin text{End}(V)$. Th...
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let $v$ be an $n$-dimensional complex inner product space. suppose $h$ is a subgroup of the symmetric group of degree $m$, and $chi :hrightarrow mathbb{c} $ is an irreducible character (not necessarily linear). denote by $v_{chi}(h)$ the symmetry class of tensors associated with $h$ and $chi$. let $k(t)in (v_{chi}(h))$ be the operator induced by $tin text{end}(v)$. the...
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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: Proceedings of the American Mathematical Society
سال: 2004
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-04-07672-5