{"title":"Coset spaces with certain q-sequences","authors":"Jiewen Chen, Bin Zhao","doi":"10.1016/j.topol.2024.109192","DOIUrl":null,"url":null,"abstract":"<div><div>Coset spaces with certain <em>q</em>-sequences are investigated. Firstly, we give some characterizations of strict <em>q</em>-spaces and strong <em>q</em>-spaces in coset spaces, and show that if <em>H</em> is a closed neutral subgroup of a topological group <em>G</em>, then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is a strict (resp., strong) <em>q</em>-space if and only if <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is an open sequential-perfect (resp., strongly sequential-perfect) preimage of a metrizable space. Secondly, we discuss metrizability of coset spaces, and prove that if <em>H</em> is a closed neutral subgroup of a topological group <em>G</em>, then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is metrizable if and only if <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is a sequential <em>csf</em>-countable <em>q</em>-space. Furthermore, if <em>H</em> is a compact subgroup of a topological group <em>G</em>, then <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is metrizable if and only if <span><math><mi>G</mi><mo>/</mo><mi>H</mi></math></span> is a hereditarily normal strict <em>q</em>-space.</div></div>","PeriodicalId":51201,"journal":{"name":"Topology and its Applications","volume":"361 ","pages":"Article 109192"},"PeriodicalIF":0.6000,"publicationDate":"2024-12-30","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/S0166864124003778","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
Abstract
Coset spaces with certain q-sequences are investigated. Firstly, we give some characterizations of strict q-spaces and strong q-spaces in coset spaces, and show that if H is a closed neutral subgroup of a topological group G, then is a strict (resp., strong) q-space if and only if is an open sequential-perfect (resp., strongly sequential-perfect) preimage of a metrizable space. Secondly, we discuss metrizability of coset spaces, and prove that if H is a closed neutral subgroup of a topological group G, then is metrizable if and only if is a sequential csf-countable q-space. Furthermore, if H is a compact subgroup of a topological group G, then is metrizable if and only if is a hereditarily normal strict q-space.
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.