Results 21 to 30 of about 236 (32)

Cohyponormal operators with the single valued extension property

International Journal of Mathematics and Mathematical Sciences, Volume 9, Issue 4, Page 659-663, 1986., 1986
It is proved that in order to find a nontrivial hyperinvariant subspace for a cohyponormal operator it suffices to make the further assumption that the operator have the single‐valued extension property.
Ridgley Lange, Shengwang Wang
wiley   +1 more source

Absolute continuity and hyponormal operators

International Journal of Mathematics and Mathematical Sciences, Volume 4, Issue 2, Page 321-335, 1981., 1981
Let T be a completely hyponormal operator, with the rectangular representation T = A + iB, on a separable Hilbert space. If 0 is not an eigenvalue of T* then T also has a polar factorization T = UP, with U unitary. It is known that A, B and U are all absolutely continuous operators.
C. R. Putnam
wiley   +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  

Hyponormality on a weighted Bergman space of an annulus with a general harmonic symbol

Open Mathematics
In this work we consider the hyponormality of Toeplitz operators on the Bergman space of the annulus with a logarithmic weight. We give necessary conditions when the symbol is of the form φ+ψ̄ $\varphi +\bar{\psi }$ where both φ and ψ are analytic on ...
Sadraoui Houcine, Halouani Borhen
doaj   +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
core   +1 more source

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  

Operators commuting with complex symmetric weighted composition operators on H 2

Concrete Operators
In this article, we initially study when an anti-linear Toeplitz operator is in the commutant of a composition operator. Primarily, we investigate weighted composition operators Wg,ψ{W}_{g,\psi } commuting with complex symmetric weighted composition ...
Bhuia Sudip Ranjan
doaj   +1 more source

Some inequalities for $(\alpha, \beta)$-normal operators in Hilbert spaces

, 2008
An operator $T$ acting on a Hilbert space is called $(\alpha ,\beta)$-normal ($0\leq \alpha \leq 1\leq \beta $) if \begin{equation*} \alpha ^{2}T^{\ast }T\leq TT^{\ast}\leq \beta ^{2}T^{\ast}T.
Dragomir, Sever S., Moslehian, Mohammad Sal   +1 more
core  

Synthesis of active distributed RC networks [PDF]

Open-circuit transfer function of two-port network expressed as rational function with real ...
Fu, J. S., Fu, Y.
core   +1 more source

The spectral properties of [ m ] -complex symmetric operators. [PDF]

J Inequal Appl, 2018
Shen J.
europepmc   +1 more source