{"title":"一般域上辛群的对合积(II):有限域","authors":"Clément de Seguins Pazzis","doi":"10.1016/j.ffa.2025.102641","DOIUrl":null,"url":null,"abstract":"<div><div>Let <em>s</em> be an <em>n</em>-dimensional symplectic form over a field <span><math><mi>F</mi></math></span> of characteristic other than 2, with <span><math><mi>n</mi><mo>></mo><mn>2</mn></math></span>.</div><div>In a previous article, we have proved that if <span><math><mi>F</mi></math></span> is infinite then every element of the symplectic group <span><math><mi>Sp</mi><mo>(</mo><mi>s</mi><mo>)</mo></math></span> is the product of four involutions if <em>n</em> is a multiple of 4 and of five involutions otherwise.</div><div>Here, we adapt this result to all finite fields with characteristic not 2, with the sole exception of the very special situation where <span><math><mi>n</mi><mo>=</mo><mn>4</mn></math></span> and <span><math><mo>|</mo><mi>F</mi><mo>|</mo><mo>=</mo><mn>3</mn></math></span>, a special case which we study extensively.</div></div>","PeriodicalId":50446,"journal":{"name":"Finite Fields and Their Applications","volume":"107 ","pages":"Article 102641"},"PeriodicalIF":1.2000,"publicationDate":"2025-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Products of involutions in symplectic groups over general fields (II): Finite fields\",\"authors\":\"Clément de Seguins Pazzis\",\"doi\":\"10.1016/j.ffa.2025.102641\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Let <em>s</em> be an <em>n</em>-dimensional symplectic form over a field <span><math><mi>F</mi></math></span> of characteristic other than 2, with <span><math><mi>n</mi><mo>></mo><mn>2</mn></math></span>.</div><div>In a previous article, we have proved that if <span><math><mi>F</mi></math></span> is infinite then every element of the symplectic group <span><math><mi>Sp</mi><mo>(</mo><mi>s</mi><mo>)</mo></math></span> is the product of four involutions if <em>n</em> is a multiple of 4 and of five involutions otherwise.</div><div>Here, we adapt this result to all finite fields with characteristic not 2, with the sole exception of the very special situation where <span><math><mi>n</mi><mo>=</mo><mn>4</mn></math></span> and <span><math><mo>|</mo><mi>F</mi><mo>|</mo><mo>=</mo><mn>3</mn></math></span>, a special case which we study extensively.</div></div>\",\"PeriodicalId\":50446,\"journal\":{\"name\":\"Finite Fields and Their Applications\",\"volume\":\"107 \",\"pages\":\"Article 102641\"},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2025-05-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Finite Fields and Their Applications\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1071579725000711\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Finite Fields and Their Applications","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1071579725000711","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
Products of involutions in symplectic groups over general fields (II): Finite fields
Let s be an n-dimensional symplectic form over a field of characteristic other than 2, with .
In a previous article, we have proved that if is infinite then every element of the symplectic group is the product of four involutions if n is a multiple of 4 and of five involutions otherwise.
Here, we adapt this result to all finite fields with characteristic not 2, with the sole exception of the very special situation where and , a special case which we study extensively.
期刊介绍:
Finite Fields and Their Applications is a peer-reviewed technical journal publishing papers in finite field theory as well as in applications of finite fields. As a result of applications in a wide variety of areas, finite fields are increasingly important in several areas of mathematics, including linear and abstract algebra, number theory and algebraic geometry, as well as in computer science, statistics, information theory, and engineering.
For cohesion, and because so many applications rely on various theoretical properties of finite fields, it is essential that there be a core of high-quality papers on theoretical aspects. In addition, since much of the vitality of the area comes from computational problems, the journal publishes papers on computational aspects of finite fields as well as on algorithms and complexity of finite field-related methods.
The journal also publishes papers in various applications including, but not limited to, algebraic coding theory, cryptology, combinatorial design theory, pseudorandom number generation, and linear recurring sequences. There are other areas of application to be included, but the important point is that finite fields play a nontrivial role in the theory, application, or algorithm.