Absolute continuity of minimal unitary dilations
نویسندگان
چکیده
منابع مشابه
Constraint Unitary Dilations and Numerical Ranges
It is shown that each contraction A on a Hilbert space H, with A + A I for some 2 R, has a unitary dilation U on H H satisfying U + U I. This is used to settle a conjecture of Halmos in the aarmative: The closure of the numerical range of each contraction A is the intersection of the closures of the numerical ranges of all unitary dilations of A. By means of the duality theory of completely pos...
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ژورنال
عنوان ژورنال: Operators and Matrices
سال: 2009
ISSN: 1846-3886
DOI: 10.7153/oam-03-28