{"title":"性质FW和群的环积:使用Schreier图的一种简单方法","authors":"Paul-Henry Leemann , Grégoire Schneeberger","doi":"10.1016/j.exmath.2022.07.001","DOIUrl":null,"url":null,"abstract":"<div><p>The group property FW stands in-between the celebrated Kazhdan’s property (T) and Serre’s property FA. Among many characterizations, it might be defined, for finitely generated groups, as having all Schreier graphs one-ended.</p><p>It follows from the work of Y. Cornulier that a finitely generated wreath product <span><math><mrow><mi>G</mi><msub><mrow><mo>≀</mo></mrow><mrow><mi>X</mi></mrow></msub><mi>H</mi></mrow></math></span> has property FW if and only if both <span><math><mi>G</mi></math></span> and <span><math><mi>H</mi></math></span> have property FW and <span><math><mi>X</mi></math></span> is finite. The aim of this paper is to give an elementary, direct and explicit proof of this fact using Schreier graphs.</p></div>","PeriodicalId":50458,"journal":{"name":"Expositiones Mathematicae","volume":null,"pages":null},"PeriodicalIF":0.8000,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0723086922000391/pdfft?md5=a25144589e5c96c13c5679a9a7e61297&pid=1-s2.0-S0723086922000391-main.pdf","citationCount":"2","resultStr":"{\"title\":\"Property FW and wreath products of groups: A simple approach using Schreier graphs\",\"authors\":\"Paul-Henry Leemann , Grégoire Schneeberger\",\"doi\":\"10.1016/j.exmath.2022.07.001\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>The group property FW stands in-between the celebrated Kazhdan’s property (T) and Serre’s property FA. Among many characterizations, it might be defined, for finitely generated groups, as having all Schreier graphs one-ended.</p><p>It follows from the work of Y. Cornulier that a finitely generated wreath product <span><math><mrow><mi>G</mi><msub><mrow><mo>≀</mo></mrow><mrow><mi>X</mi></mrow></msub><mi>H</mi></mrow></math></span> has property FW if and only if both <span><math><mi>G</mi></math></span> and <span><math><mi>H</mi></math></span> have property FW and <span><math><mi>X</mi></math></span> is finite. The aim of this paper is to give an elementary, direct and explicit proof of this fact using Schreier graphs.</p></div>\",\"PeriodicalId\":50458,\"journal\":{\"name\":\"Expositiones Mathematicae\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.8000,\"publicationDate\":\"2022-12-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.sciencedirect.com/science/article/pii/S0723086922000391/pdfft?md5=a25144589e5c96c13c5679a9a7e61297&pid=1-s2.0-S0723086922000391-main.pdf\",\"citationCount\":\"2\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Expositiones Mathematicae\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0723086922000391\",\"RegionNum\":4,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Expositiones Mathematicae","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0723086922000391","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
Property FW and wreath products of groups: A simple approach using Schreier graphs
The group property FW stands in-between the celebrated Kazhdan’s property (T) and Serre’s property FA. Among many characterizations, it might be defined, for finitely generated groups, as having all Schreier graphs one-ended.
It follows from the work of Y. Cornulier that a finitely generated wreath product has property FW if and only if both and have property FW and is finite. The aim of this paper is to give an elementary, direct and explicit proof of this fact using Schreier graphs.
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