{"title":"On the descent for quadratic and bilinear forms","authors":"Ahmed Laghribi, Diksha Mukhija","doi":"10.1002/mana.202400061","DOIUrl":null,"url":null,"abstract":"<p>This paper is devoted to the study of the descent problem in the spirit of conjectures proposed by Kahn in characteristic different from 2. The descent problem seeks conditions under which a <span></span><math>\n <semantics>\n <mi>K</mi>\n <annotation>$K$</annotation>\n </semantics></math>-form (quadratic or bilinear) is defined over <span></span><math>\n <semantics>\n <mi>F</mi>\n <annotation>$F$</annotation>\n </semantics></math> for a field extension <span></span><math>\n <semantics>\n <mrow>\n <mi>K</mi>\n <mo>/</mo>\n <mi>F</mi>\n </mrow>\n <annotation>$K/F$</annotation>\n </semantics></math>. We study this problem in a complete manner for <span></span><math>\n <semantics>\n <mi>K</mi>\n <annotation>$K$</annotation>\n </semantics></math>-quadratic and bilinear forms up to dimension 4 when <span></span><math>\n <semantics>\n <mi>F</mi>\n <annotation>$F$</annotation>\n </semantics></math> is a field of characteristic 2 and <span></span><math>\n <semantics>\n <mi>K</mi>\n <annotation>$K$</annotation>\n </semantics></math> is the function field of a projective quadric.</p>","PeriodicalId":49853,"journal":{"name":"Mathematische Nachrichten","volume":"298 6","pages":"2037-2059"},"PeriodicalIF":0.8000,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mathematische Nachrichten","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/mana.202400061","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
Abstract
This paper is devoted to the study of the descent problem in the spirit of conjectures proposed by Kahn in characteristic different from 2. The descent problem seeks conditions under which a -form (quadratic or bilinear) is defined over for a field extension . We study this problem in a complete manner for -quadratic and bilinear forms up to dimension 4 when is a field of characteristic 2 and is the function field of a projective quadric.
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