Results 11 to 20 of about 5,890,937 (282)
Components of linear-fractional composition operators [PDF]
Journal of Mathematical Analysis and Applications, 2003 Let \(\phi\) denote a holomorphic function on the open unit disc \(U\) in the complex plane with \(\phi(U) \subset U\). The composition operator \(C_{\phi}(f):=f \circ \phi\) is bounded in the Hardy space \(H^2\). Denote by \(\text{comp} (H^2)\) the collection of all composition operators on \(H^2\) endowed with the metric induced by the operator norm.
Bourdon, Paul S
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Linear Combinations of Composition Operators on the Bloch Spaces [PDF]
Canadian Journal of Mathematics, 2011 Abstract We characterize the compactness of linear combinations of analytic composition operators on the Bloch space. We also study their boundedness and compactness on the little Bloch space.
Takuya Hosokawa +2 more
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Composition of some positive linear integral operators
Demonstratio MathematicaThis article is devoted to constructing sequences of integral operators with the same Voronovskaja formula as the generalized Baskakov operators, but having different behavior in other respects.
Acu Ana-Maria, Rasa Ioan, Sofonea Florin
doaj +2 more sources
Complex symmetric weighted composition operators on the Hardy space [PDF]
, 2020 summary:This paper identifies a class of complex symmetric weighted composition operators on $H^2(\mathbb {D})$ that includes both the unitary and the Hermitian weighted composition operators, as well as a class of normal weighted composition operators ...
Zhou, Ze-Hua, Jiang, Cao, Han, Shi-An
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Norms of linear-fractional composition operators [PDF]
Transactions of the American Mathematical Society, 2003 Summary: We obtain a representation for the norm of the composition operator \(C_\phi\) on the Hardy space \(H^2\) whenever \(\phi\) is a linear-fractional mapping of the form \(\phi(z) = b/(cz +d)\). The representation shows that, for such mappings \(\phi\), the norm of \(C_\phi\) always exceeds the essential norm of \(C_\phi\).
Bourdon, Paul S. +3 more
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Some inequalities for the Euclidean operator radius of two operators in Hilbert spaces [PDF]
, 2006 Some sharp bounds for the Euclidean operator radius of two bounded linear operators in Hilbert spaces are given. Their connection with Kittaneh’s recent results which provide sharp upper and lower bounds for the numerical radius of linear operators are ...
Dragomir, Sever S
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On the composition and decomposition of positive linear operators (VII)
Applicable Analysis and Discrete Mathematics, 2021 In the present paper we study the compositions of the piecewise linear interpolation operator S?n and the Beta-type operator B?n, namely An:= S?n ?B?n and Gn := B?n ? S?n. Voronovskaya type theorems for the operators An and Gn are proved, substantially improving some corresponding known results.
Acu, Ana Maria, Raşa, Ioan
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Norm and Numerical Radius Inequalities for Two Linear Operators in Hilbert Spaces [PDF]
, 2008 Some inequalities for the norm and numerical radius of two bounded linear operators in Hilbert spaces are ...
Dragomir, Sever S
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Cyclic behaviour of Volterra composition operators [PDF]
, 2011 We determine the cyclic behaviour of Volterra composition operators, which are defined as $(V_\phif)(x) =\int_0^{\phi(x)}f(t) dt$, $f ? L^p[0, 1]$, 1\leq p <\infty$,where $?$ is a measurable self-map of [0, 1].
Stanislav Shkarin +5 more
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Linear and Logarithmic Time Compositions of Quantum Many-Body Operators [PDF]
Physical Review Letters, 2017 We develop a generalized framework for constructing many-body-interaction operations either in linear time, or in logarithmic time with a linear number of ancilla qubits. Exact gate decompositions are given in particular for Pauli strings, many-control Toffoli gates, number-~and parity-conserving interactions, Unitary Coupled Cluster operations, and ...
Motzoi, F. +2 more
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