Results 41 to 50 of about 137 (130)
On the Möbius invariant principal functions of Pincus [PDF]
Opuscula MathematicaIn this semi-expository short note, we prove that the only homogeneous pure hyponormal operator \(T\) with \(\operatorname{rank} (T^*T-TT^*) =1\), modulo unitary equivalence, is the unilateral shift.
Sagar Ghosh, Gadadhar Misra
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A Note on Unbounded Hyponormal Composition Operators in L2-Spaces
Journal of Function Spaces and Applications, 2012 We construct an unbounded hyponormal composition operator Cϕ in L2-space such that the domains of Cϕ2 and Cϕ2 are trivial.
Piotr Budzyński
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The Spectra of Unbounded Hyponormal Operators [PDF]
Proceedings of the American Mathematical Society, 1972 A bounded operator T T on a Hilbert space is said to be completely hyponormal if
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On hyponormal operators in Krein spaces [PDF]
Archivum Mathematicum, 2019 Summary: In this paper the hyponormal operators on Krein spaces are introduced. We state conditions for the hyponormality of bounded operators focusing, in particular, on those operators \(T\) for which there exists a fundamental decomposition \(\mathcal{K}=\mathcal{K}^+\oplus\mathcal{K}^-\) of the Krein space \(\mathcal{K}\) with \(\mathcal{K}^+\) and
Esmeral, Kevin +3 more
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Class of (n, m)-Power-D-Hyponormal Operators in Hilbert Space
International Journal of Analysis and Applications, 2020 In this paper, we introduce a new classes of operators acting on a complex Hilbert space H, denoted by [(n, m)DH], called (n, m)-power-D-hyponormal associated with a Drazin inversible operator using its Drazin inverse.
Cherifa Chellali, Abdelkader Benali
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Higher-Order Extensions of C-Hyponormality via n-Quasi-C-Hyponormal Operators
MathematicsIn this paper, we investigate generalizations and extensions of C-hyponormal operators, focusing on the class of n-quasi-C-hyponormal operators. We provide a detailed structural analysis, including decomposition results that split an operator into a C ...
Sid Ahmed Ould Ahmed Mahmoud +1 more
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A characterization of operators via Berezin symbol and related questions
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2023 In this paper, we characterize the hyponormal operators with regard to Berezin symbol and reproducing kernel. Also, we demonstrate several Berezin number inequalities for bounded linear operators.
Yamancı Ulaş
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Orbits of hyponormal operators.
Michigan Mathematical Journal, 1997 A bounded linear operator \(A\) on the Hilbert space \(H\) is hypercyclic if there is a vector \(x\in H\) such that \[ \text{Orb}(A,x)=\{A^nx: n=0,1,2,\cdots\} \] is dense in \(H\). In this case we say that \(x\) is a hypercyclic vector for \(A\). We say that \(A\) is supercyclic if there is a vector \(x\in H\) such that \[ \{\lambda A^nx:\lambda\in ...
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Journal of Inequalities and ApplicationsA Drazin invertible operator T on a Hilbert space is said to be of class [ D H ] $[DH] $ if T ∗ T D ≥ T D T ∗ $T^{*}T^{D}\geq T^{D}T^{*} $ . Our findings contribute to the deeper understanding of D-hyponormal operators by proving several key inequalities
Mansour Dana +2 more
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Almost 𝜶-Hyponormal Operators with Weyl Spectrum of Area Zero
International Journal of Mathematics and Mathematical Sciences, 2011 We define the class of almost 𝛼-hyponormal operators and prove that for an operator 𝑇 in this class, (𝑇∗𝑇)𝛼−(𝑇𝑇∗)𝛼 is trace-class and its trace is zero when 𝛼∈(0,1] and the area of the Weyl spectrum is zero.
Vasile Lauric
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