Results 31 to 40 of about 431 (69)
, 2015 It is proved that each bounded injective bilateral weighted shift $W$ satisfying the equality $W^{*n}W^{n}=(W^{*}W)^{n}$ for some integer $n\geq 2$ is quasinormal. For any integer $n\geq 2$, an example of a bounded non-quasinormal weighted shift $A$ on a
Pietrzycki, Paweł
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Hyponormal Toeplitz operators with polynomial symbols on weighted Bergman spaces
, 2014 In this note we consider the hyponormality of Toeplitz operators Tφ on weighted Bergman space Aα2(D) with symbol in the class of functions f+g¯ with polynomials f and g.MSC:47B20, 47B35.
I. Hwang, Jongrak Lee, S. W. Park
semanticscholar +1 more source
Spectra of subnormal pairs [PDF]
, 2007 In this short note we present an example related to joint spectra of subnormal pairs of bounded operators. A counterexample to the equality between Taylor's spectrum and the closure of the defect spectrum is given. This example is related to the author's
Krzysztof Rudol
core
Moments from their very truncations
, 2007 It is known that positive definiteness is not enough for the multidimensional moment problem to be solved. We would like throw in to the garden of existing in this matter so far results one more, a result which takes into considerations the utmost ...
Szafraniec, F. H.
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Complex symmetric weighted composition Lambert type operators on L^2(Σ)
, 2018 In this paper we obtain the polar decomposition and the Aluthge transform of a weighted composition Lambert type operator MwEMuCφ on L2(Σ) . In addition, we study the complex symmetry of these types of operators induced by triple (w,u,φ) .
M. Jabbarzadeh, M. Moradi
semanticscholar +1 more source
On ergodic operator means in Banach spaces
, 2015 We consider a large class of operator means and prove that a number of ergodic theorems, as well as growth estimates known for particular cases, continue to hold in the general context under fairly mild regularity conditions. The methods developed in the
Aleman, Alexandru, Suciu, Laurian
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Generalized Derivations and Norm Equality in Normed Ideals [PDF]
, 2011 2000 Mathematics Subject Classification: 47A10, 47A12, 47A30, 47B10, 47B20, 47B37, 47B47, 47D50.We compare the norm of a generalized derivation on a Hilbert space with the norm of its restrictions to Schatten norm ...
Barraa, Mohamed
core
A NOTE ON P-SYMMETRIC OPERATORS
, 2016 Let L(H) denote the algebra of operators on a complex infinite dimensional Hilbert space H into itself. In this paper, we study the class of operators A ∈ L(H) which satisfy the following property, AT = TA implies AT ∗ = T ∗A for all T ∈ C1(H) (trace ...
S. Bouali +3 more
semanticscholar +1 more source
Propagation phenomena for mono-weakly hyponormal operator pairs
Operators and Matrices, 2019 In this note, we strengthen some of flatness results for mono-polynomially hyponormal and mono-weakly 2-hyponormal 2-variable weighted shifts in [15, 16, 17]. Mathematics subject classification (2010): 47B20, 47B37, 47A13.
Yongjiang Duan, Shichan Pang, S. Y. Wang
semanticscholar +1 more source
Bishop's property (β) for paranormal operators
, 2009 For an operator T on a separable complex Hilbert space H , we say that T has Bishop’s property (β) if for any open subset D ⊂ C and any sequence of analytic functions fn : D →H such as ‖(T −z) fn(z)‖→ 0 as n→∞ uniformly on every compact subset K ⊂D ...
A. Uchiyama, K. Tanahashi
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