{"title":"数域整数环高 K 理论中的还原映射","authors":"Soumyadip Sahu","doi":"10.1016/j.jpaa.2024.107771","DOIUrl":null,"url":null,"abstract":"<div><p>This article studies the reduction maps in the higher <em>K</em>-theory of the ring of integers in a number field arising from the canonical reduction maps at nonzero prime ideals. It proves an explicit density estimate for the subset of primes where the images of a fixed collection of elements vanish. Our result applies to a collection of elements possibly having different degrees and suggests that the linearly independent elements of global <em>K</em>-theory exhibit mutually independent reduction patterns. We also relate the reduction map in <em>K</em>-theory to the reduction map in stable cohomology of general linear groups. This connection allows us to examine the pullback of Quillen's <em>e</em>-classes in the cohomology of the stable general linear group over a finite field. During the proof of the main result, we construct the smallest Galois extension which trivializes a Galois cohomology class of degree one, and show that the linear independence of classes results in disjointness of corresponding field extensions.</p></div>","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Reduction map in the higher K-theory of the rings of integers in number fields\",\"authors\":\"Soumyadip Sahu\",\"doi\":\"10.1016/j.jpaa.2024.107771\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>This article studies the reduction maps in the higher <em>K</em>-theory of the ring of integers in a number field arising from the canonical reduction maps at nonzero prime ideals. It proves an explicit density estimate for the subset of primes where the images of a fixed collection of elements vanish. Our result applies to a collection of elements possibly having different degrees and suggests that the linearly independent elements of global <em>K</em>-theory exhibit mutually independent reduction patterns. We also relate the reduction map in <em>K</em>-theory to the reduction map in stable cohomology of general linear groups. This connection allows us to examine the pullback of Quillen's <em>e</em>-classes in the cohomology of the stable general linear group over a finite field. During the proof of the main result, we construct the smallest Galois extension which trivializes a Galois cohomology class of degree one, and show that the linear independence of classes results in disjointness of corresponding field extensions.</p></div>\",\"PeriodicalId\":0,\"journal\":{\"name\":\"\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0,\"publicationDate\":\"2024-07-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022404924001683\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022404924001683","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Reduction map in the higher K-theory of the rings of integers in number fields
This article studies the reduction maps in the higher K-theory of the ring of integers in a number field arising from the canonical reduction maps at nonzero prime ideals. It proves an explicit density estimate for the subset of primes where the images of a fixed collection of elements vanish. Our result applies to a collection of elements possibly having different degrees and suggests that the linearly independent elements of global K-theory exhibit mutually independent reduction patterns. We also relate the reduction map in K-theory to the reduction map in stable cohomology of general linear groups. This connection allows us to examine the pullback of Quillen's e-classes in the cohomology of the stable general linear group over a finite field. During the proof of the main result, we construct the smallest Galois extension which trivializes a Galois cohomology class of degree one, and show that the linear independence of classes results in disjointness of corresponding field extensions.