{"title":"有限群作为等距群的实现及极小性问题","authors":"Pedro J. Chocano","doi":"10.1002/mana.202400287","DOIUrl":null,"url":null,"abstract":"<p>A finite group <span></span><math>\n <semantics>\n <mi>G</mi>\n <annotation>$G$</annotation>\n </semantics></math> is said to be realized by a finite subset <span></span><math>\n <semantics>\n <mi>V</mi>\n <annotation>$V$</annotation>\n </semantics></math> of a Euclidean space <span></span><math>\n <semantics>\n <msup>\n <mi>R</mi>\n <mi>n</mi>\n </msup>\n <annotation>$\\mathbb {R}^n$</annotation>\n </semantics></math> if the isometry group of <span></span><math>\n <semantics>\n <mi>V</mi>\n <annotation>$V$</annotation>\n </semantics></math> is isomorphic to <span></span><math>\n <semantics>\n <mi>G</mi>\n <annotation>$G$</annotation>\n </semantics></math>. We prove that every finite group can be realized by a finite subset <span></span><math>\n <semantics>\n <mrow>\n <mi>V</mi>\n <mo>⊂</mo>\n <msup>\n <mi>R</mi>\n <mrow>\n <mo>|</mo>\n <mi>G</mi>\n <mo>|</mo>\n </mrow>\n </msup>\n </mrow>\n <annotation>$V\\subset \\mathbb {R}^{|G|}$</annotation>\n </semantics></math> consisting of <span></span><math>\n <semantics>\n <mrow>\n <mrow>\n <mo>|</mo>\n <mi>G</mi>\n <mo>|</mo>\n <mo>(</mo>\n <mo>|</mo>\n <mi>S</mi>\n <mo>|</mo>\n </mrow>\n <mo>+</mo>\n <mrow>\n <mn>1</mn>\n <mo>)</mo>\n <mo>(</mo>\n </mrow>\n <mo>≤</mo>\n <mrow>\n <mo>|</mo>\n <mi>G</mi>\n <mo>|</mo>\n <mo>(</mo>\n </mrow>\n <msub>\n <mi>log</mi>\n <mn>2</mn>\n </msub>\n <mrow>\n <mo>(</mo>\n <mo>|</mo>\n <mi>G</mi>\n <mo>|</mo>\n <mo>)</mo>\n </mrow>\n <mo>+</mo>\n <mrow>\n <mn>1</mn>\n <mo>)</mo>\n <mo>)</mo>\n </mrow>\n </mrow>\n <annotation>$|G|(|S|+1) (\\le |G|(\\log _2(|G|)+1))$</annotation>\n </semantics></math> points, where <span></span><math>\n <semantics>\n <mi>S</mi>\n <annotation>$S$</annotation>\n </semantics></math> is a generating system for <span></span><math>\n <semantics>\n <mi>G</mi>\n <annotation>$G$</annotation>\n </semantics></math>. We define <span></span><math>\n <semantics>\n <mrow>\n <mi>α</mi>\n <mo>(</mo>\n <mi>G</mi>\n <mo>)</mo>\n </mrow>\n <annotation>$\\alpha (G)$</annotation>\n </semantics></math> as the minimum number of points required to realize <span></span><math>\n <semantics>\n <mi>G</mi>\n <annotation>$G$</annotation>\n </semantics></math> in <span></span><math>\n <semantics>\n <msup>\n <mi>R</mi>\n <mi>m</mi>\n </msup>\n <annotation>$\\mathbb {R}^m$</annotation>\n </semantics></math> for some <span></span><math>\n <semantics>\n <mi>m</mi>\n <annotation>$m$</annotation>\n </semantics></math>. We establish that <span></span><math>\n <semantics>\n <mrow>\n <mo>|</mo>\n <mi>V</mi>\n <mo>|</mo>\n </mrow>\n <annotation>$|V|$</annotation>\n </semantics></math> provides a sharp upper bound for <span></span><math>\n <semantics>\n <mrow>\n <mi>α</mi>\n <mo>(</mo>\n <mi>G</mi>\n <mo>)</mo>\n </mrow>\n <annotation>$\\alpha (G)$</annotation>\n </semantics></math> when considering minimal generating sets. Finally, we explore the relationship between <span></span><math>\n <semantics>\n <mrow>\n <mi>α</mi>\n <mo>(</mo>\n <mi>G</mi>\n <mo>)</mo>\n </mrow>\n <annotation>$\\alpha (G)$</annotation>\n </semantics></math> and the isometry dimension of <span></span><math>\n <semantics>\n <mi>G</mi>\n <annotation>$G$</annotation>\n </semantics></math>, that is, defined as the least dimension of the Euclidean space in which <span></span><math>\n <semantics>\n <mi>G</mi>\n <annotation>$G$</annotation>\n </semantics></math> can be realized.</p>","PeriodicalId":49853,"journal":{"name":"Mathematische Nachrichten","volume":"298 2","pages":"419-426"},"PeriodicalIF":0.8000,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mana.202400287","citationCount":"0","resultStr":"{\"title\":\"Realization of finite groups as isometry groups and problems of minimality\",\"authors\":\"Pedro J. Chocano\",\"doi\":\"10.1002/mana.202400287\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>A finite group <span></span><math>\\n <semantics>\\n <mi>G</mi>\\n <annotation>$G$</annotation>\\n </semantics></math> is said to be realized by a finite subset <span></span><math>\\n <semantics>\\n <mi>V</mi>\\n <annotation>$V$</annotation>\\n </semantics></math> of a Euclidean space <span></span><math>\\n <semantics>\\n <msup>\\n <mi>R</mi>\\n <mi>n</mi>\\n </msup>\\n <annotation>$\\\\mathbb {R}^n$</annotation>\\n </semantics></math> if the isometry group of <span></span><math>\\n <semantics>\\n <mi>V</mi>\\n <annotation>$V$</annotation>\\n </semantics></math> is isomorphic to <span></span><math>\\n <semantics>\\n <mi>G</mi>\\n <annotation>$G$</annotation>\\n </semantics></math>. We prove that every finite group can be realized by a finite subset <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>V</mi>\\n <mo>⊂</mo>\\n <msup>\\n <mi>R</mi>\\n <mrow>\\n <mo>|</mo>\\n <mi>G</mi>\\n <mo>|</mo>\\n </mrow>\\n </msup>\\n </mrow>\\n <annotation>$V\\\\subset \\\\mathbb {R}^{|G|}$</annotation>\\n </semantics></math> consisting of <span></span><math>\\n <semantics>\\n <mrow>\\n <mrow>\\n <mo>|</mo>\\n <mi>G</mi>\\n <mo>|</mo>\\n <mo>(</mo>\\n <mo>|</mo>\\n <mi>S</mi>\\n <mo>|</mo>\\n </mrow>\\n <mo>+</mo>\\n <mrow>\\n <mn>1</mn>\\n <mo>)</mo>\\n <mo>(</mo>\\n </mrow>\\n <mo>≤</mo>\\n <mrow>\\n <mo>|</mo>\\n <mi>G</mi>\\n <mo>|</mo>\\n <mo>(</mo>\\n </mrow>\\n <msub>\\n <mi>log</mi>\\n <mn>2</mn>\\n </msub>\\n <mrow>\\n <mo>(</mo>\\n <mo>|</mo>\\n <mi>G</mi>\\n <mo>|</mo>\\n <mo>)</mo>\\n </mrow>\\n <mo>+</mo>\\n <mrow>\\n <mn>1</mn>\\n <mo>)</mo>\\n <mo>)</mo>\\n </mrow>\\n </mrow>\\n <annotation>$|G|(|S|+1) (\\\\le |G|(\\\\log _2(|G|)+1))$</annotation>\\n </semantics></math> points, where <span></span><math>\\n <semantics>\\n <mi>S</mi>\\n <annotation>$S$</annotation>\\n </semantics></math> is a generating system for <span></span><math>\\n <semantics>\\n <mi>G</mi>\\n <annotation>$G$</annotation>\\n </semantics></math>. We define <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>α</mi>\\n <mo>(</mo>\\n <mi>G</mi>\\n <mo>)</mo>\\n </mrow>\\n <annotation>$\\\\alpha (G)$</annotation>\\n </semantics></math> as the minimum number of points required to realize <span></span><math>\\n <semantics>\\n <mi>G</mi>\\n <annotation>$G$</annotation>\\n </semantics></math> in <span></span><math>\\n <semantics>\\n <msup>\\n <mi>R</mi>\\n <mi>m</mi>\\n </msup>\\n <annotation>$\\\\mathbb {R}^m$</annotation>\\n </semantics></math> for some <span></span><math>\\n <semantics>\\n <mi>m</mi>\\n <annotation>$m$</annotation>\\n </semantics></math>. We establish that <span></span><math>\\n <semantics>\\n <mrow>\\n <mo>|</mo>\\n <mi>V</mi>\\n <mo>|</mo>\\n </mrow>\\n <annotation>$|V|$</annotation>\\n </semantics></math> provides a sharp upper bound for <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>α</mi>\\n <mo>(</mo>\\n <mi>G</mi>\\n <mo>)</mo>\\n </mrow>\\n <annotation>$\\\\alpha (G)$</annotation>\\n </semantics></math> when considering minimal generating sets. Finally, we explore the relationship between <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>α</mi>\\n <mo>(</mo>\\n <mi>G</mi>\\n <mo>)</mo>\\n </mrow>\\n <annotation>$\\\\alpha (G)$</annotation>\\n </semantics></math> and the isometry dimension of <span></span><math>\\n <semantics>\\n <mi>G</mi>\\n <annotation>$G$</annotation>\\n </semantics></math>, that is, defined as the least dimension of the Euclidean space in which <span></span><math>\\n <semantics>\\n <mi>G</mi>\\n <annotation>$G$</annotation>\\n </semantics></math> can be realized.</p>\",\"PeriodicalId\":49853,\"journal\":{\"name\":\"Mathematische Nachrichten\",\"volume\":\"298 2\",\"pages\":\"419-426\"},\"PeriodicalIF\":0.8000,\"publicationDate\":\"2024-11-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mana.202400287\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Mathematische Nachrichten\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1002/mana.202400287\",\"RegionNum\":3,\"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":"Mathematische Nachrichten","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/mana.202400287","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
摘要
一个有限群G $G$被认为是由欧几里德空间R n $\mathbb {R}^n$的一个有限子集V $V$来实现的,如果V $V$的等距群与G同构$G$。我们证明了每一个有限群都可以由一个有限子集V∧R | G | $V\subset \mathbb {R}^{|G|}$组成| g | (| s | + 1)(≤| g | (log2 (| G |) + 1)) $|G|(|S|+1) (\le |G|(\log _2(|G|)+1))$其中S $S$是G $G$的生成系统。我们将α (G) $\alpha (G)$定义为在R m $\mathbb {R}^m$中实现G $G$所需的最小点数M $m$。我们建立了| V | $|V|$在考虑最小发电机组时,为α (G) $\alpha (G)$提供了一个明显的上界。最后,我们探讨了α (G) $\alpha (G)$与G $G$等距维数的关系,即:定义为可实现G $G$的欧几里得空间的最小维数。
Realization of finite groups as isometry groups and problems of minimality
A finite group is said to be realized by a finite subset of a Euclidean space if the isometry group of is isomorphic to . We prove that every finite group can be realized by a finite subset consisting of points, where is a generating system for . We define as the minimum number of points required to realize in for some . We establish that provides a sharp upper bound for when considering minimal generating sets. Finally, we explore the relationship between and the isometry dimension of , that is, defined as the least dimension of the Euclidean space in which can be realized.
期刊介绍:
Mathematische Nachrichten - Mathematical News publishes original papers on new results and methods that hold prospect for substantial progress in mathematics and its applications. All branches of analysis, algebra, number theory, geometry and topology, flow mechanics and theoretical aspects of stochastics are given special emphasis. Mathematische Nachrichten is indexed/abstracted in Current Contents/Physical, Chemical and Earth Sciences; Mathematical Review; Zentralblatt für Mathematik; Math Database on STN International, INSPEC; Science Citation Index