Results 51 to 60 of about 137 (130)
Hyponormal operators quasisimilar to an isometry [PDF]
Transactions of the American Mathematical Society, 1985 An expression for the multiplicity of an arbitrary contraction is presented. It is in terms of the isometries which can be densely intertwined to the given contraction. This is then used to obtain a generalization of a result of Sz.-Nagy and Foiaş concerning the existence of a
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Nonlinear Analysis: Algorithm, Convergence, and Applications 2014
, 2014 Abstract and Applied Analysis, Volume 2014, Issue 1, 2014.
Yisheng Song +4 more
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On p-quasi-hyponormal operators
Linear Algebra and its Applications, 2007 For an infinite-dimensional Hilbert space \(H\), let \(B(H)\) denote the algebra of all bounded linear operators on \(H\).
Duggal, B.P., Jeon, In Ho
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A Review on Classes of Composition Operators
پژوهشهای ریاضی, 2020 Introduction In 1976, A. Lambert characterized subnormal weighted shifts. Then he studied hyponormal weighted composition operators on in 1986 and in 1988 subnormal composition operators studied again by him. Recently, A. Lambert, et al., have published
Mohammadreza Azimi
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Mathematics: The S. cerevisae for Natural Science Research
, 2012 International Journal of Mathematics and Mathematical Sciences, Volume 2012, Issue 1, 2012.
Shigeru Kanemitsu +3 more
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$\alpha$-Supraposinormality of Operators in Dense Norm-Attainable Classes
Universal Journal of Mathematics and Applications, 2019 The notion of supraposinormality was introduced by Rhaly in a superclass of posinormal operators. In this paper, we give an extension of this notion of supraposinormality to $\alpha$-supraposinormality of operators in the dense norm-attainable class.
Benard Okelo
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On Commutators of Isometries and Hyponormal Operators [PDF]
Journal of Sciences, Islamic Republic of Iran, 1989 A sufficient condition is obtained for two isometries to be unitarily equivalent.
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Some Estimates of Certain Subnormal and Hyponormal Derivations
International Journal of Mathematics and Mathematical Sciences, 2008 We prove that if 𝐴 and 𝐵∗ are subnormal operators and 𝑋 is a bounded linear operator such that 𝐴𝑋−𝑋𝐵 is a Hilbert-Schmidt operator, then 𝑓(𝐴)𝑋−𝑋𝑓(𝐵) is also a Hilbert-Schmidt operator and ‖𝑓(𝐴)𝑋−𝑋𝑓(𝐵)‖2≤𝐿‖𝐴𝑋−𝑋𝐵‖2 for 𝑓 belongs to a certain class of ...
Vasile Lauric
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International Journal of Mathematics and Mathematical Sciences, 2003 We introduce the concept of quasireducible operators. Basic properties and illustrative examples are considered in some detail in order to situate the class of quasireducible operators in its due place.
C. S. Kubrusly
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Exponential Function of a bounded Linear Operator on a Hilbert Space.
مجلة بغداد للعلوم, 2014 In this paper, we introduce an exponential of an operator defined on a Hilbert space H, and we study its properties and find some of properties of T inherited to exponential operator, so we study the spectrum of exponential operator e^T according to the
Baghdad Science Journal
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