Diagonals of normal operators with finite spectrum
نویسندگان
چکیده
منابع مشابه
Diagonals of normal operators with finite spectrum.
Let X={lambda1, ..., lambdaN} be a finite set of complex numbers, and let A be a normal operator with spectrum X that acts on a separable Hilbert space H. Relative to a fixed orthonormal basis e1, e2, ... for H, A gives rise to a matrix whose diagonal is a sequence d=(d1, d2, ...) with the property that each of its terms dn belongs to the convex hull of X. Not all sequences with that property c...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2007
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.0605367104