Advances in Operator Theory最新文献_第3页

On the conjugate weight function and ultradifferentiable classes of entire functions 共轭权函数与整个函数的超可微类。

IF 0.7

Advances in Operator Theory Pub Date : 2026-06-15 DOI: 10.1007/s43036-026-00503-y

Gerhard Schindl

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引用次数: 0

A characterization of amenability property of WAP(S) in locally convex spaces 局部凸空间中WAP(S)的适应性表征

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Advances in Operator Theory Pub Date : 2026-06-08 DOI: 10.1007/s43036-026-00507-8

Khadime Salame

引用次数: 0

Grothendieck–Pietsch composition results for multiple summing operators 多个求和算子的Grothendieck-Pietsch组合结果

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Advances in Operator Theory Pub Date : 2026-06-03 DOI: 10.1007/s43036-026-00511-y

Dumitru Popa

引用次数: 0

Residual-weighted decomposition of positive operators 正算子的残差加权分解

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Advances in Operator Theory Pub Date : 2026-05-29 DOI: 10.1007/s43036-026-00509-6

James Tian

{"title":"Residual-weighted decomposition of positive operators","authors":"James Tian","doi":"10.1007/s43036-026-00509-6","DOIUrl":"10.1007/s43036-026-00509-6","url":null,"abstract":"<div>This paper investigates an iterative rank-one decomposition scheme for positive operators on a Hilbert space based on a residual-weighted congruence update. At each step the operator is compressed along a chosen unit vector while remaining inside the positive cone, and the resulting map defines a monotone dynamical system on the cone of positive operators. We prove that the associated residuals admit a canonical telescoping decomposition into rank-one terms and a limiting positive operator, and we identify this limit together with an exact energy identity expressing the defect between the initial and limiting operators as a convergent series of rank-one contributions. In the case where the iteration exhausts the operator, the residual directions form a Parseval frame for the natural range space, yielding a constructive procedure that produces Parseval frames without spectral calculus. We further solve the inverse problem by characterizing those decreasing chains with rank-one steps that arise from such dynamics via an intrinsic normalization condition involving the Moore–Penrose inverse. For trace-class operators we obtain a scalar energy identity and show that mild greedy or density conditions on the chosen directions guarantee exhaustion. An application to reproducing kernel Hilbert spaces illustrates the abstract results.</div>","PeriodicalId":44371,"journal":{"name":"Advances in Operator Theory","volume":"11 3","pages":""},"PeriodicalIF":0.7,"publicationDate":"2026-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148173337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Affine AP-frames and stationary random processes 仿射ap帧与平稳随机过程

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Advances in Operator Theory Pub Date : 2026-05-29 DOI: 10.1007/s43036-026-00514-9

Hernán D. Centeno, Juan M. Medina

引用次数: 0

K-positivity preserver of matrix polynomials 矩阵多项式的k -正守恒

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Advances in Operator Theory Pub Date : 2026-05-29 DOI: 10.1007/s43036-026-00512-x

Philipp J. di Dio, Lars-Luca Langer

{"title":"K-positivity preserver of matrix polynomials","authors":"Philipp J. di Dio, Lars-Luca Langer","doi":"10.1007/s43036-026-00512-x","DOIUrl":"10.1007/s43036-026-00512-x","url":null,"abstract":"<div>For any closed (Ksubseteq mathbb {R}^n), recently all K-positivity preserver have been characterized, i.e., all linear operators (T:mathbb {R}[x_1,dots ,x_n]rightarrow mathbb {R}[x_1,dots ,x_n]) such that (Tpge 0) on K for all (pge 0) on K. An important extension of polynomials (mathbb {R}[x_1,dots ,x_n]) with real coefficients are polynomials (mathbb {R}^{mtimes m}[x_1,dots ,x_n]) with matrix coefficients. Non-negativity on K for matrix polynomials with Hermitian coefficients (textrm{Herm}_m) is then (p(x)succeq 0) for all (xin K). In the current work, we investigate linear operators (T:textrm{Herm}_m[x_1,dots ,x_n]rightarrow textrm{Herm}_m[x_1,dots ,x_n]). We focus on matrix K-positivity preserver, i.e., (Tpsucceq 0) on K for all (psucceq 0) on K. For (K=mathbb {R}^n) and compact sets (Ksubseteq mathbb {R}^n), we give characterizations of matrix K-positivity preservers. We discuss the difference between the real and the matrix coefficient case and where our proof fails for general sets (Ksubseteq mathbb {R}^n) with (Kne mathbb {R}^n) and K non-compact.</div>","PeriodicalId":44371,"journal":{"name":"Advances in Operator Theory","volume":"11 3","pages":""},"PeriodicalIF":0.7,"publicationDate":"2026-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s43036-026-00512-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148173336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fredholmness of singular integral operators with continuous coefficients on Banach function spaces over the real line 实线上Banach函数空间上连续系数奇异积分算子的收敛性

IF 0.7

Advances in Operator Theory Pub Date : 2026-05-25 DOI: 10.1007/s43036-026-00510-z

Márcio Valente

引用次数: 0

Interpolating sequences for weighted spaces of analytic functions on Banach spaces Banach空间上解析函数加权空间的插值序列

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Advances in Operator Theory Pub Date : 2026-05-07 DOI: 10.1007/s43036-026-00505-w

Mario P. Maletzki

引用次数: 0

Rapid decay for odometers 里程表的快速衰减