{"title":"Expansion of normal subsets of odd-order elements in finite groups","authors":"Chris Parker, Jack Saunders","doi":"10.1112/jlms.70534","DOIUrl":null,"url":null,"abstract":"<p>Let <span></span><math>\n <semantics>\n <mi>G</mi>\n <annotation>$G$</annotation>\n </semantics></math> be a finite group and <span></span><math>\n <semantics>\n <mi>K</mi>\n <annotation>$K$</annotation>\n </semantics></math> a normal subset consisting of odd-order elements. The rational closure of <span></span><math>\n <semantics>\n <mi>K</mi>\n <annotation>$K$</annotation>\n </semantics></math>, denoted <span></span><math>\n <semantics>\n <msub>\n <mi>D</mi>\n <mi>K</mi>\n </msub>\n <annotation>$\\mathbf {D}_K$</annotation>\n </semantics></math>, is the set of elements <span></span><math>\n <semantics>\n <mrow>\n <mi>x</mi>\n <mo>∈</mo>\n <mi>G</mi>\n </mrow>\n <annotation>$x \\in G$</annotation>\n </semantics></math> with the property that <span></span><math>\n <semantics>\n <mrow>\n <mo>⟨</mo>\n <mi>x</mi>\n <mo>⟩</mo>\n <mo>=</mo>\n <mo>⟨</mo>\n <mi>y</mi>\n <mo>⟩</mo>\n </mrow>\n <annotation>$\\langle x \\rangle = \\langle y \\rangle$</annotation>\n </semantics></math> for some <span></span><math>\n <semantics>\n <mi>y</mi>\n <annotation>$y$</annotation>\n </semantics></math> in <span></span><math>\n <semantics>\n <mi>K</mi>\n <annotation>$K$</annotation>\n </semantics></math>. If <span></span><math>\n <semantics>\n <mrow>\n <msup>\n <mi>K</mi>\n <mn>2</mn>\n </msup>\n <mo>⊆</mo>\n <msub>\n <mi>D</mi>\n <mi>K</mi>\n </msub>\n </mrow>\n <annotation>$K^2 \\subseteq \\mathbf {D}_K$</annotation>\n </semantics></math>, we prove that <span></span><math>\n <semantics>\n <mrow>\n <mo>⟨</mo>\n <mi>K</mi>\n <mo>⟩</mo>\n </mrow>\n <annotation>$\\langle K \\rangle$</annotation>\n </semantics></math> is soluble.</p>","PeriodicalId":49989,"journal":{"name":"Journal of the London Mathematical Society-Second Series","volume":"113 4","pages":""},"PeriodicalIF":1.2000,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://londmathsoc.onlinelibrary.wiley.com/doi/epdf/10.1112/jlms.70534","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the London Mathematical Society-Second Series","FirstCategoryId":"100","ListUrlMain":"https://londmathsoc.onlinelibrary.wiley.com/doi/10.1112/jlms.70534","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
Let be a finite group and a normal subset consisting of odd-order elements. The rational closure of , denoted , is the set of elements with the property that for some in . If , we prove that is soluble.
期刊介绍:
The Journal of the London Mathematical Society has been publishing leading research in a broad range of mathematical subject areas since 1926. The Journal welcomes papers on subjects of general interest that represent a significant advance in mathematical knowledge, as well as submissions that are deemed to stimulate new interest and research activity.