منابع مشابه
Existence of Non-subnormal Polynomially Hyponormal Operators
In 1950, P. R. Halmos, motivated in part by the successful development of the theory of normal operators, introduced the notions of subnormality and hyponormality for (bounded) Hilbert space operators. An operator T is subnormal if it is the restriction of a normal operator to an invariant subspace; T is hyponormal if T*T > TT*. It is a simple matrix calculation to verify that subnormality impl...
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ژورنال
عنوان ژورنال: Bulletin of the American Mathematical Society
سال: 1983
ISSN: 0273-0979
DOI: 10.1090/s0273-0979-1983-15144-3