发布求助
文献互助 智能选刊 最新文献

Commentationes Mathematicae Universitatis Carolinae最新文献

筛选
英文 中文
Revisiting linear Weingarten spacelike submanifolds immersed in a locally symmetric semi-Riemannian space 重温沉浸在局部对称半黎曼空间中的线性Weingarten类空间子流形
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-11-13 DOI: 10.14712/1213-7243.2023.013
Weiller F. C.  Barboza, Henrique F. de Lima, Marco A. L. Velásquez
{"title":"Revisiting linear Weingarten spacelike submanifolds immersed in a locally symmetric semi-Riemannian space","authors":"Weiller F. C.  Barboza, Henrique F. de Lima, Marco A. L. Velásquez","doi":"10.14712/1213-7243.2023.013","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.013","url":null,"abstract":"In this paper, we deal with $n$-dimensional complete linear Weingarten spacelike submanifolds immersed with parallel normalized mean curvature vector field and flat normal bundle in a locally symmetric semi-Riemannian space $L_{p}^{n+p}$ of index $p>1$, which obeys some curvature constraints (such an ambient space can be regarded as an extension of a semi-Riemannian space form). Under appropriate hypothesis, we are able to prove that such a spacelike submanifold is either totally umbilical or isometric to an isoparametric submanifold of the ambient space. For this, we use three main core analytical tools: a suitable version of the Omori--Yau maximum principle, parabolicity with respect to a modified Cheng--Yau operator and a certain integrability property.","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":"39 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136348203","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
Universality, complexity and asymptotically uniformly smooth Banach spaces 通用性、复杂性与渐近一致光滑Banach空间
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-11-13 DOI: 10.14712/1213-7243.2023.015
R Causey, Gilles Lancien
{"title":"Universality, complexity and asymptotically uniformly smooth Banach spaces","authors":"R Causey, Gilles Lancien","doi":"10.14712/1213-7243.2023.015","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.015","url":null,"abstract":"For $1 < p le infty$, we show the existence of a Banach space which is both injectively and surjectively universal for the class of all separable Banach spaces with an equivalent $p$-asymptotically uniformly smooth norm. We prove that this class is analytic complete in the class of separable Banach spaces. These results extend previous works by N. J. Kalton, D. Werner and O. Kurka in the case $p=infty$.","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":"8 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134993028","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: 1
A countably cellular topological group all of whose countable subsets are closed need not be $mathbb{R}$-factorizable 一个可数元胞拓扑群，其所有可数子集都是闭的，不必是$mathbb{R}$-可因数的
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-11-13 DOI: 10.14712/1213-7243.2023.016
Mikhail  Tkachenko
{"title":"A countably cellular topological group all of whose countable subsets are closed need not be $mathbb{R}$-factorizable","authors":"Mikhail  Tkachenko","doi":"10.14712/1213-7243.2023.016","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.016","url":null,"abstract":"We construct a Hausdorff topological group $G$ such that $aleph_1$ is a precalibre of $G$ (hence, $G$ has countable cellularity), all countable subsets of $G$ are closed and $C$-embedded in $G$, but $G$ is not $mathbb{R}$-factorizable. This solves Problem 8.6.3 from the book ``Topological Groups and Related Structures\" (2008) in the negative.","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":"32 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136348618","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
A note on functional tightness and minitightness of space of the $G$-permutation degree 关于$G$-置换度空间的功能密性和微密性的一个注记
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-11-13 DOI: 10.14712/1213-7243.2023.019
Dimitrios N.  Georgiou, Nodirbek K. Mamadaliev, Rustam M. Zhuraev
{"title":"A note on functional tightness and minitightness of space of the $G$-permutation degree","authors":"Dimitrios N.  Georgiou, Nodirbek K. Mamadaliev, Rustam M. Zhuraev","doi":"10.14712/1213-7243.2023.019","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.019","url":null,"abstract":"We study the behavior of the minimal tightness and functional tightness of topological spaces under the influence of the functor of the permutation degree. Analytically: a) We introduce the notion of $tau$-open sets and investigate some basic properties of them. b) We prove that if the map $fcolon Xrightarrow Y$ is $tau$-continuous, then the map $SP^{n}fcolon SP^n X rightarrow SP^n Y$ is also $tau$-continuous. c) We show that the functor $SP^n$ preserves the functional tightness and the minimal tightness of compacts. d) Finally, we give some facts and properties on $tau$-bounded spaces. More precisely, we prove that the functor of permutation degree $SP^n$ preserves the property of being $tau$-bounded.","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":"88 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136346959","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
Special sets of reals and weak forms of normality on Isbell--Mrówka spaces Isbell- Mrówka空间上的实数和弱正规形式的特殊集合
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-11-13 DOI: 10.14712/1213-7243.2023.014
Vinicius  de Oliveira Rodrigues, Victor dos Santos Ronchim, Paul J. Szeptycki
{"title":"Special sets of reals and weak forms of normality on Isbell--Mrówka spaces","authors":"Vinicius  de Oliveira Rodrigues, Victor dos Santos Ronchim, Paul J. Szeptycki","doi":"10.14712/1213-7243.2023.014","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.014","url":null,"abstract":"We recall some classical results relating normality and some natural weakenings of normality in $Psi$-spaces over almost disjoint families of branches in the Cantor tree to special sets of reals like $Q$-sets, $lambda$-sets and $sigma$-sets. We introduce a new class of special sets of reals which corresponds to the corresponding almost disjoint family of branches being $aleph_0$-separated. This new class fits between $lambda$-sets and perfectly meager sets. We also discuss conditions for an almost disjoint family $mathcal A$ being potentially almost-normal (pseudonormal), in the sense that $mathcal A$ is almost-normal (pseudonormal) in some c.c.c. forcing extension.","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":"39 13","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136348198","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
Quasicontinuous spaces Quasicontinuous空间
IF 0.2
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-04-28 DOI: 10.14712/1213-7243.2023.005
Jing  Lu, Bin Zhao, K. Wang, Dongsheng Zhao
{"title":"Quasicontinuous spaces","authors":"Jing  Lu, Bin Zhao, K. Wang, Dongsheng Zhao","doi":"10.14712/1213-7243.2023.005","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.005","url":null,"abstract":"","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42850427","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
Mal'tsev--Neumann products of semi-simple classes of rings Mal’tsev——半简单环类的Neumann乘积
IF 0.2
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-04-28 DOI: 10.14712/1213-7243.2023.004
Barry James  Gardner
{"title":"Mal'tsev--Neumann products of semi-simple classes of rings","authors":"Barry James  Gardner","doi":"10.14712/1213-7243.2023.004","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.004","url":null,"abstract":"","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":"1 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41617559","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
Degree polynomial for vertices in a graph and its behavior under graph operations 图中顶点的次多项式及其在图操作下的行为
IF 0.2
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-04-28 DOI: 10.14712/1213-7243.2023.006
Reza  Jafarpour-Golzari
{"title":"Degree polynomial for vertices in a graph and its behavior under graph operations","authors":"Reza  Jafarpour-Golzari","doi":"10.14712/1213-7243.2023.006","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.006","url":null,"abstract":"","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45793125","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
On sets of discontinuities of functions continuous on all lines 在所有直线上连续的函数的不连续集合上
IF 0.2
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-04-28 DOI: 10.14712/1213-7243.2023.007
Luděk  Zajíček
{"title":"On sets of discontinuities of functions continuous on all lines","authors":"Luděk  Zajíček","doi":"10.14712/1213-7243.2023.007","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.007","url":null,"abstract":"","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47010581","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
Some isomorphic properties in projective tensor products 投影张量积中的一些同构性质
IF 0.2
Commentationes Mathematicae Universitatis Carolinae Pub Date : 2023-04-28 DOI: 10.14712/1213-7243.2023.008
Ioana  Ghenciu
{"title":"Some isomorphic properties in projective tensor products","authors":"Ioana  Ghenciu","doi":"10.14712/1213-7243.2023.008","DOIUrl":"https://doi.org/10.14712/1213-7243.2023.008","url":null,"abstract":"","PeriodicalId":44396,"journal":{"name":"Commentationes Mathematicae Universitatis Carolinae","volume":" ","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44548301","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
首页 上一页 下一页 尾页
0
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整，为了账户安全，请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
请完成安全验证×
相关产品
×
本文献相关产品
联系我们：info@booksci.cn Book学术提供免费学术资源搜索服务，方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号：481959085
Book学术官方微信