On quasisimilarity for subnormal operators
نویسندگان
چکیده
منابع مشابه
Hyperinvariant Subspaces for Some Subnormal Operators
In this article we employ a technique originated by Enflo in 1998 and later modified by the authors to study the hyperinvariant subspace problem for subnormal operators. We show that every “normalized” subnormal operator S such that either {(S∗nSn)1/n} does not converge in the SOT to the identity operator or {(SnS∗n)1/n} does not converge in the SOT to zero has a nontrivial hyperinvariant subsp...
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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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We continue our study of hyperinvariant subspaces for rationally cyclic subnormal operators. We establish a connection between hyperinvariant subspaces and weak-star continuous point evaluations on the commutant. Introduction. Let A be a compact subset of the complex plane C and let R(K) denote the algebra of rational functions with poles off K. For a positive measure p with support in K let R2...
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ژورنال
عنوان ژورنال: Illinois Journal of Mathematics
سال: 1980
ISSN: 0019-2082
DOI: 10.1215/ijm/1256047484