PARANORMAL CONTRACTIONS AND INVARIANT SUBSPACES
نویسندگان
چکیده
منابع مشابه
Paranormal Contractions and Invariant Subspaces
It is shown that if a paranormal contraction T has no nontrivial invariant subspace, then it is a proper contraction. Moreover, the nonnegative operator Q = T 2∗T 2 − 2T ∗T + I also is a proper contraction. If a quasihyponormal contraction has no nontrivial invariant subspace then, in addition, its defect operator D is a proper contraction and its itself-commutator is a trace-class strict contr...
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ژورنال
عنوان ژورنال: Journal of the Korean Mathematical Society
سال: 2003
ISSN: 0304-9914
DOI: 10.4134/jkms.2003.40.6.933