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WEYL`S THEOREM, TENSOR PRODUCT, FUGLEDE-PUTNAM THEOREM AND CONTINUITY SPECTRUM FOR k-QUASI CLASS An* OPERATO
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 Title & Authors
WEYL`S THEOREM, TENSOR PRODUCT, FUGLEDE-PUTNAM THEOREM AND CONTINUITY SPECTRUM FOR k-QUASI CLASS An* OPERATO
Hoxha, Ilmi; Braha, Naim Latif;
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 Abstract
An operator , is said to belong to k-quasi class operator if for some positive integer n and some positive integer k. First, we will see some properties of this class of operators and prove Weyl`s theorem for algebraically k-quasi class . Second, we consider the tensor product for k-quasi class , giving a necessary and sufficient condition for to be a k-quasi class , when T and S are both non-zero operators. Then, the existence of a nontrivial hyperinvariant subspace of k-quasi class operator will be shown, and it will also be shown that if X is a Hilbert-Schmidt operator, A and are k-quasi class operators such that AX
 Keywords
k-quasi class operators;Weyl`s theorem;a-Weyl`s theorem;polaroid operators;tensor products;Fuglede-Putnam theorem;hyperinvariant;continuity spectrum;
 Language
English
 Cited by
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