Corners of multidimensional numerical ranges
نویسنده
چکیده
The n-dimensional numerical range of a densely defined linear operator T on a complex Hilbert space H is the set of vectors in Cn of the form (〈Te1, e1〉, . . . , 〈Ten, en〉), where e1, . . . , en is an orthonormal system in H, consisting of vectors from the domain of T . We prove that the components of every corner point of the n-dimensional numerical range are eigenvalues of T .
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