Quasinormal Operators and Reflexive Subspaces
نویسندگان
چکیده
منابع مشابه
Hyperinvariant subspaces and quasinilpotent operators
For a bounded linear operator on Hilbert space we define a sequence of the so-called weakly extremal vectors. We study the properties of weakly extremal vectors and show that the orthogonality equation is valid for weakly extremal vectors. Also we show that any quasinilpotent operator $T$ has an hypernoncyclic vector, and so $T$ has a nontrivial hyperinvariant subspace.
متن کاملhyperinvariant subspaces and quasinilpotent operators
for a bounded linear operator on hilbert space we define a sequence of the so-called weakly extremal vectors. we study the properties of weakly extremal vectors and show that the orthogonality equation is valid for weakly extremal vectors. also we show that any quasinilpotent operator $t$ has an hypernoncyclic vector, and so $t$ has a nontrivial hyperinvariant subspace.
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ژورنال
عنوان ژورنال: Rocky Mountain Journal of Mathematics
سال: 2003
ISSN: 0035-7596
DOI: 10.1216/rmjm/1181075470