{"title":"q-bic形式","authors":"Raymond Cheng","doi":"10.1016/j.jalgebra.2025.03.031","DOIUrl":null,"url":null,"abstract":"<div><div>A <em>q-bic form</em> is a pairing <span><math><mi>V</mi><mo>×</mo><mi>V</mi><mo>→</mo><mi>k</mi></math></span> that is linear in the second variable and <em>q</em>-power Frobenius linear in the first; here, <em>V</em> is a vector space over a field <strong>k</strong> containing the finite field <span><math><msub><mrow><mi>F</mi></mrow><mrow><msup><mrow><mi>q</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></msub></math></span>. This article develops a geometric theory of <em>q</em>-bic forms in the spirit of that of bilinear forms. I find two filtrations intrinsically attached to a <em>q</em>-bic form, with which I define a series of numerical invariants. These are used to classify, study automorphism group schemes of, and describe specialization relations in the parameter space of <em>q</em>-bic forms.</div></div>","PeriodicalId":14888,"journal":{"name":"Journal of Algebra","volume":"675 ","pages":"Pages 196-236"},"PeriodicalIF":0.8000,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"q-bic forms\",\"authors\":\"Raymond Cheng\",\"doi\":\"10.1016/j.jalgebra.2025.03.031\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>A <em>q-bic form</em> is a pairing <span><math><mi>V</mi><mo>×</mo><mi>V</mi><mo>→</mo><mi>k</mi></math></span> that is linear in the second variable and <em>q</em>-power Frobenius linear in the first; here, <em>V</em> is a vector space over a field <strong>k</strong> containing the finite field <span><math><msub><mrow><mi>F</mi></mrow><mrow><msup><mrow><mi>q</mi></mrow><mrow><mn>2</mn></mrow></msup></mrow></msub></math></span>. This article develops a geometric theory of <em>q</em>-bic forms in the spirit of that of bilinear forms. I find two filtrations intrinsically attached to a <em>q</em>-bic form, with which I define a series of numerical invariants. These are used to classify, study automorphism group schemes of, and describe specialization relations in the parameter space of <em>q</em>-bic forms.</div></div>\",\"PeriodicalId\":14888,\"journal\":{\"name\":\"Journal of Algebra\",\"volume\":\"675 \",\"pages\":\"Pages 196-236\"},\"PeriodicalIF\":0.8000,\"publicationDate\":\"2025-04-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Algebra\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0021869325001772\",\"RegionNum\":2,\"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":"Journal of Algebra","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0021869325001772","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
A q-bic form is a pairing that is linear in the second variable and q-power Frobenius linear in the first; here, V is a vector space over a field k containing the finite field . This article develops a geometric theory of q-bic forms in the spirit of that of bilinear forms. I find two filtrations intrinsically attached to a q-bic form, with which I define a series of numerical invariants. These are used to classify, study automorphism group schemes of, and describe specialization relations in the parameter space of q-bic forms.
期刊介绍:
The Journal of Algebra is a leading international journal and publishes papers that demonstrate high quality research results in algebra and related computational aspects. Only the very best and most interesting papers are to be considered for publication in the journal. With this in mind, it is important that the contribution offer a substantial result that will have a lasting effect upon the field. The journal also seeks work that presents innovative techniques that offer promising results for future research.