Topology and its Applications最新文献

A note on crossing changes and delta-moves for virtual knots 关于虚拟结的交叉变化和delta移动的注释

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-10-02 DOI: 10.1016/j.topol.2025.109622

Ryuji Higa

引用次数: 0

Attractors as a bridge from topological properties to long-term behavior in dynamical systems 吸引子是动力系统从拓扑性质到长期行为的桥梁

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-10-02 DOI: 10.1016/j.topol.2025.109604

Aliasghar Sarizadeh

引用次数: 0

Some notes on topological rings and their groups of units 拓扑环及其单位群的若干注释

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-25 DOI: 10.1016/j.topol.2025.109600

Abolfazl Tarizadeh

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引用次数: 0

Extensions of increasing bounded uniformly continuous functions 递增有界一致连续函数的扩展

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-24 DOI: 10.1016/j.topol.2025.109599

Kaori Yamazaki

引用次数: 0

Large C*-polyhedrons in C*-algebras C*代数中的大C*多面体

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-22 DOI: 10.1016/j.topol.2025.109598

Clayton Suguio Hida

{"title":"Large C*-polyhedrons in C*-algebras","authors":"Clayton Suguio Hida","doi":"10.1016/j.topol.2025.109598","DOIUrl":"10.1016/j.topol.2025.109598","url":null,"abstract":"<div><div>A classical polyhedron in a Banach space is a collection of points with a distinctive geometric separation property: each point in the set can be separated from the others by a closed convex set. This concept reflects the interplay between convexity and the geometry of Banach spaces. In this article, we introduce and study a noncommutative analogue of this notion, based on the concept of <span><math><msup><mrow><mi>C</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math></span>-convexity, a generalization of classical convexity within the setting of <span><math><msup><mrow><mi>C</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math></span>-algebras. We define the notion of a <span><math><msup><mrow><mi>C</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math></span>-polyhedron as a family of elements in a <span><math><msup><mrow><mi>C</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math></span>-algebra that satisfies a similar separation property with respect to closed <span><math><msup><mrow><mi>C</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math></span>-convex sets. Our main goal is to investigate the maximal possible cardinality of <span><math><msup><mrow><mi>C</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math></span>-polyhedrons in various <span><math><msup><mrow><mi>C</mi></mrow><mrow><mo>⁎</mo></mrow></msup></math></span>-algebras, with particular attention to classical examples from the theory of operator algebras, such as the algebras of compact and bounded operators on a Hilbert space.</div></div>","PeriodicalId":51201,"journal":{"name":"Topology and its Applications","volume":"375 ","pages":"Article 109598"},"PeriodicalIF":0.5,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145118518","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

Equicontinuity, rigidity, and distality of trajectories 轨迹的等连续性、刚性和距离性

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-16 DOI: 10.1016/j.topol.2025.109595

Khadija Ben Rejeb , Seif Mezzi

引用次数: 0

On partial knots for symmetric unions 关于对称并集的部分节

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-12 DOI: 10.1016/j.topol.2025.109593

Christoph Lamm , Toshifumi Tanaka

引用次数: 0

Connecting discrete Morse functions via birth-death transitions 通过出生-死亡转换连接离散莫尔斯函数

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-12 DOI: 10.1016/j.topol.2025.109594

Chong Zheng

引用次数: 0

Weakly and strongly reversible spaces 弱和强可逆空间

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-12 DOI: 10.1016/j.topol.2025.109596

Miloš S. Kurilić

引用次数: 0

On χ-slice pretzel links 关于χ-slice pretzel链接

IF 0.5 4区数学

Topology and its Applications Pub Date : 2025-09-11 DOI: 10.1016/j.topol.2025.109578

Sophia Fanelle, Evan Huang, Ben Huenemann, Weizhe Shen, Jonathan Simone, Hannah Turner

引用次数: 0