某些类型余集空间的三空间特性

IF 0.6 4区 数学 Q3 MATHEMATICS Topology and its Applications Pub Date : 2024-07-17 DOI:10.1016/j.topol.2024.109021
Jiewen Chen, Xuewei Ling, Bin Zhao
{"title":"某些类型余集空间的三空间特性","authors":"Jiewen Chen,&nbsp;Xuewei Ling,&nbsp;Bin Zhao","doi":"10.1016/j.topol.2024.109021","DOIUrl":null,"url":null,"abstract":"<div><p>In this paper, some three-space properties of (compactly-fibered, neutrally-fibered) coset spaces are considered. Let <span><math><mi>X</mi><mo>=</mo><mi>G</mi><mo>/</mo><mi>H</mi></math></span> be a coset space and <em>K</em> a closed subgroup of <em>G</em> with <span><math><mi>H</mi><mo>⊂</mo><mi>K</mi></math></span>. It is mainly shown that (1) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is neutrally-fibered, then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is second-countable ⇔ <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> are second-countable; (2) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is compactly-fibered such that all compact (resp., countably compact) subspaces of <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> are metrizable, then all compact (resp., countably compact) subspaces of <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> are metrizable; (3) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is neutrally-fibered such that <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> is second-countable and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> an <span><math><msub><mrow><mi>ℵ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>-space (resp., cosmic), then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is an <span><math><msub><mrow><mi>ℵ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>-space (resp., cosmic); (4) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is neutrally-fibered such that <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> is second-countable and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> has a star-countable <em>cs</em>-network, then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> has a star-countable <em>cs</em>-network; (5) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is compactly-fibered such that <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> is locally compact metrizable and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> stratifiable (resp., <em>k</em>-semi-stratifiable), then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is stratifiable (resp., <em>k</em>-semi-stratifiable).</p></div>","PeriodicalId":51201,"journal":{"name":"Topology and its Applications","volume":"355 ","pages":"Article 109021"},"PeriodicalIF":0.6000,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Three-space properties of some kinds of coset spaces\",\"authors\":\"Jiewen Chen,&nbsp;Xuewei Ling,&nbsp;Bin Zhao\",\"doi\":\"10.1016/j.topol.2024.109021\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>In this paper, some three-space properties of (compactly-fibered, neutrally-fibered) coset spaces are considered. Let <span><math><mi>X</mi><mo>=</mo><mi>G</mi><mo>/</mo><mi>H</mi></math></span> be a coset space and <em>K</em> a closed subgroup of <em>G</em> with <span><math><mi>H</mi><mo>⊂</mo><mi>K</mi></math></span>. It is mainly shown that (1) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is neutrally-fibered, then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is second-countable ⇔ <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> are second-countable; (2) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is compactly-fibered such that all compact (resp., countably compact) subspaces of <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> are metrizable, then all compact (resp., countably compact) subspaces of <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> are metrizable; (3) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is neutrally-fibered such that <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> is second-countable and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> an <span><math><msub><mrow><mi>ℵ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>-space (resp., cosmic), then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is an <span><math><msub><mrow><mi>ℵ</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>-space (resp., cosmic); (4) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is neutrally-fibered such that <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> is second-countable and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> has a star-countable <em>cs</em>-network, then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> has a star-countable <em>cs</em>-network; (5) If <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is compactly-fibered such that <span><math><mi>K</mi><mo>/</mo><mi>H</mi></math></span> is locally compact metrizable and <span><math><mi>G</mi><mo>/</mo><mi>K</mi></math></span> stratifiable (resp., <em>k</em>-semi-stratifiable), then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is stratifiable (resp., <em>k</em>-semi-stratifiable).</p></div>\",\"PeriodicalId\":51201,\"journal\":{\"name\":\"Topology and its Applications\",\"volume\":\"355 \",\"pages\":\"Article 109021\"},\"PeriodicalIF\":0.6000,\"publicationDate\":\"2024-07-17\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Topology and its Applications\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0166864124002062\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Topology and its Applications","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0166864124002062","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0

摘要

本文考虑了(紧凑纤维、中性纤维)余集空间的一些三空间性质。主要证明:(1)如果是中性纤维的,那么是第二可数的 ⇔ 和 是第二可数的;(2)如果是紧凑纤维的,使得和 的所有紧凑(或可数紧凑)子空间都是可元空间,那么和 的所有紧凑(或可数紧凑)子空间都是可元空间;(3)如果是中性纤维的,使得是第二可数的和 是-空间(或宇宙空间),那么是-空间(或宇宙空间);(4)如果是中性纤维的,使得是第二可数的和 是-空间(或宇宙空间),那么是-空间(或宇宙空间);(5)如果是中性纤维的,使得是第二可数的和 是-空间(或宇宙空间),那么是-空间(或宇宙空间);(6)如果是中性纤维的,使得是第二可数的和 是-空间(或宇宙空间),那么是-空间(或宇宙空间)、宇宙),那么是一个-空间(也可以说是宇宙);(4)如果是中性纤维的,以致是第二可数的,并且有一个星形可数-网络,那么有一个星形可数-网络;(5)如果是紧凑纤维的,以致是局部紧凑可元空间和可分层的(也可以说是-可分层的),那么是可分层的(也可以说是-可分层的)。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
Three-space properties of some kinds of coset spaces

In this paper, some three-space properties of (compactly-fibered, neutrally-fibered) coset spaces are considered. Let X=G/H be a coset space and K a closed subgroup of G with HK. It is mainly shown that (1) If G/H is neutrally-fibered, then G/H is second-countable ⇔ K/H and G/K are second-countable; (2) If G/H is compactly-fibered such that all compact (resp., countably compact) subspaces of K/H and G/K are metrizable, then all compact (resp., countably compact) subspaces of G/H are metrizable; (3) If G/H is neutrally-fibered such that K/H is second-countable and G/K an 0-space (resp., cosmic), then G/H is an 0-space (resp., cosmic); (4) If G/H is neutrally-fibered such that K/H is second-countable and G/K has a star-countable cs-network, then G/H has a star-countable cs-network; (5) If G/H is compactly-fibered such that K/H is locally compact metrizable and G/K stratifiable (resp., k-semi-stratifiable), then G/H is stratifiable (resp., k-semi-stratifiable).

求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
CiteScore
1.20
自引率
33.30%
发文量
251
审稿时长
6 months
期刊介绍: Topology and its Applications is primarily concerned with publishing original research papers of moderate length. However, a limited number of carefully selected survey or expository papers are also included. The mathematical focus of the journal is that suggested by the title: Research in Topology. It is felt that it is inadvisable to attempt a definitive description of topology as understood for this journal. Certainly the subject includes the algebraic, general, geometric, and set-theoretic facets of topology as well as areas of interactions between topology and other mathematical disciplines, e.g. topological algebra, topological dynamics, functional analysis, category theory. Since the roles of various aspects of topology continue to change, the non-specific delineation of topics serves to reflect the current state of research in topology. At regular intervals, the journal publishes a section entitled Open Problems in Topology, edited by J. van Mill and G.M. Reed. This is a status report on the 1100 problems listed in the book of the same name published by North-Holland in 1990, edited by van Mill and Reed.
期刊最新文献
Editorial Board The Rudin-Kiesler pre-order and the Pixley-Roy spaces over ultrafilters The uniform convergence topology on separable subsets Relatively functionally countable subsets of products Extendability to Marczewski-Burstin countably representable ideals
×
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
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 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 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1