Complex Analysis and Operator Theory最新文献_第4页

Characterization of Forward, Vanishing, and Reverse Bergman Carleson Measures using Sparse Domination 利用稀疏主宰法表征正向、消失和反向伯格曼-卡列松量纲

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-28 DOI: 10.1007/s11785-024-01565-7

Hamzeh Keshavarzi

引用次数: 0

Commutativity and Compactness of kth Order Slant Toeplitz Operators k 阶斜托普利兹算子的交换性与紧凑性

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-27 DOI: 10.1007/s11785-024-01570-w

M. Premjit Singh, Khumballambam Priyobarta Singh, Elija Chongtham, Oinam Nilbir Singh

引用次数: 0

A Nagy–Foias Program for a C.N.U. $$Gamma _n$$ -Contraction C.N.U. $$Gamma _n$$ -协约的纳吉-福阿斯程序

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-27 DOI: 10.1007/s11785-024-01568-4

Bappa Bisai, Sourav Pal

{"title":"A Nagy–Foias Program for a C.N.U. $$Gamma _n$$ -Contraction","authors":"Bappa Bisai, Sourav Pal","doi":"10.1007/s11785-024-01568-4","DOIUrl":"https://doi.org/10.1007/s11785-024-01568-4","url":null,"abstract":"A tuple of commuting Hilbert space operators ((S_1, ldots , S_{n-1}, P)) having the closed symmetrized polydisc $$begin{aligned} Gamma _n = left{ left( sum _{i=1}^{n}z_i, sum limits _{1le i<jle n} z_iz_j, ldots , prod _{i=1}^{n}z_iright) : |z_i|le 1, ; ; ; 1le i le n-1 right} end{aligned}$$as a spectral set is called a (Gamma _n)-contraction. From the literature we have that a point ((s_1, ldots , s_{n-1},p)) in (Gamma _n) can be represented as (s_i=c_i+pc_{n-i}) for some ((c_1, ldots , c_{n-1}) in Gamma _{n-1}). We construct a minimal (Gamma _n)-isometric dilation for a particular class of c.n.u. (Gamma _n)-contractions ((S_1, ldots , S_{n-1},P)) and obtain a functional model for them. With the help of this model we express each (S_i) as (S_i=C_i+PC_{n-i}), which is an operator theoretic analogue of the scalar result. We also produce an abstract model for a different class of c.n.u. (Gamma _n)-contractions satisfying (S_i^*P=PS_i^*) for each i. By exhibiting a counter example we show that such abstract model may not exist if we drop the hypothesis that (S_i^*P=PS_i^*). We apply this abstract model to achieve a complete unitary invariant for such c.n.u. (Gamma _n)-contractions. Additionally, we present different necessary conditions for dilation and a sufficient condition under which a commuting tuple ((S_1, ldots , S_{n-1},P)) becomes a (Gamma _n)-contraction. The entire program goes parallel to the operator theoretic program developed by Sz.-Nagy and Foias for a c.n.u. contraction.","PeriodicalId":50654,"journal":{"name":"Complex Analysis and Operator Theory","volume":"28 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On The Monotony of Struve Functions 论斯特鲁夫函数的单调性

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-25 DOI: 10.1007/s11785-024-01563-9

Erhan Deniz, Róbert Szász

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Dirichlet Problem for Nonlinear Higher-Order Equations in Upper Half Plane 上半平面非线性高阶方程的 Dirichlet 问题

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-25 DOI: 10.1007/s11785-024-01566-6

Pelin Ayşe Gökgöz

引用次数: 0

A Gap Condition for the Zeros and Singularities of a Certain Class of Products 某类积的零点和奇点的间隙条件

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-22 DOI: 10.1007/s11785-024-01564-8

Szymon Ignaciuk, Maciej Parol

引用次数: 0

Numerical Radius and Norm Bounds via the Moore-Penrose Inverse 通过摩尔-彭罗斯逆计算数值半径和规范界限

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-21 DOI: 10.1007/s11785-024-01560-y

Mohammad Sababheh, Dragan S. Djordjević, Hamid Reza Moradi

引用次数: 0

Rawnsley’s $$varepsilon $$ -Function on a Class of Bounded Hartogs Domains and its Applications Rawnsley's $$varepsilon $$ -Function on a Class of Bounded Hartogs Domains 及其应用

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-21 DOI: 10.1007/s11785-024-01562-w

Shuo Zhang

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Representations of Some Classes of Quaternionic Hyperholomorphic Functions 几类四元超全貌函数的表示

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-18 DOI: 10.1007/s11785-024-01561-x

Tetiana Kuzmenko, Vitalii Shpakivskyi

引用次数: 0

Weighted Composition Semigroups on Spaces of Continuous Functions and Their Subspaces 连续函数空间及其子空间上的加权合成半群

IF 0.8 4区数学

Complex Analysis and Operator Theory Pub Date : 2024-06-11 DOI: 10.1007/s11785-024-01559-5

Karsten Kruse

{"title":"Weighted Composition Semigroups on Spaces of Continuous Functions and Their Subspaces","authors":"Karsten Kruse","doi":"10.1007/s11785-024-01559-5","DOIUrl":"https://doi.org/10.1007/s11785-024-01559-5","url":null,"abstract":"This paper is dedicated to weighted composition semigroups on spaces of continuous functions and their subspaces. We consider semigroups induced by semiflows and semicocycles on Banach spaces (mathcal {F}(Omega )) of continuous functions on a Hausdorff space (Omega ) such that the norm-topology is stronger than the compact-open topology like the Hardy spaces, the weighted Bergman spaces, the Dirichlet space, the Bloch type spaces, the space of bounded Dirichlet series and weighted spaces of continuous or holomorphic functions. It was shown by Gallardo-Gutiérrez, Siskakis and Yakubovich that there are no non-trivial norm-strongly continuous weighted composition semigroups on Banach spaces (mathcal {F}(mathbb {D})) of holomorphic functions on the open unit disc (mathbb {D}) such that (H^{infty }subset mathcal {F}(mathbb {D})subset mathcal {B}_{1}) where (H^{infty }) is the Hardy space of bounded holomorphic functions on (mathbb {D}) and (mathcal {B}_{1}) the Bloch space. However, we show that there are non-trivial weighted composition semigroups on such spaces which are strongly continuous w.r.t. the mixed topology between the norm-topology and the compact-open topology. We study such weighted composition semigroups in the general setting of Banach spaces of continuous functions and derive necessary and sufficient conditions on the spaces involved, the semiflows and semicocycles for strong continuity w.r.t. the mixed topology and as a byproduct for norm-strong continuity as well. Moreover, we give several characterisations of their generator and their space of norm-strong continuity.","PeriodicalId":50654,"journal":{"name":"Complex Analysis and Operator Theory","volume":"61 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141509724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0