{"title":"$mathbf{C^{2}}$ -Lusin approximation of strongly convex functions(强凸函数的鲁辛近似","authors":"Daniel Azagra, Marjorie Drake, Piotr Hajłasz","doi":"10.1007/s00222-024-01252-6","DOIUrl":null,"url":null,"abstract":"<p>We prove that if <span>\\(u:\\mathbb{R}^{n}\\to \\mathbb{R}\\)</span> is strongly convex, then for every <span>\\(\\varepsilon >0\\)</span> there is a strongly convex function <span>\\(v\\in C^{2}(\\mathbb{R}^{n})\\)</span> such that <span>\\(|\\{u\\neq v\\}|<\\varepsilon \\)</span> and <span>\\(\\Vert u-v\\Vert _{\\infty}<\\varepsilon \\)</span>.</p>","PeriodicalId":14429,"journal":{"name":"Inventiones mathematicae","volume":"24 1","pages":""},"PeriodicalIF":2.6000,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"$\\\\mathbf{C^{2}}$ -Lusin approximation of strongly convex functions\",\"authors\":\"Daniel Azagra, Marjorie Drake, Piotr Hajłasz\",\"doi\":\"10.1007/s00222-024-01252-6\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>We prove that if <span>\\\\(u:\\\\mathbb{R}^{n}\\\\to \\\\mathbb{R}\\\\)</span> is strongly convex, then for every <span>\\\\(\\\\varepsilon >0\\\\)</span> there is a strongly convex function <span>\\\\(v\\\\in C^{2}(\\\\mathbb{R}^{n})\\\\)</span> such that <span>\\\\(|\\\\{u\\\\neq v\\\\}|<\\\\varepsilon \\\\)</span> and <span>\\\\(\\\\Vert u-v\\\\Vert _{\\\\infty}<\\\\varepsilon \\\\)</span>.</p>\",\"PeriodicalId\":14429,\"journal\":{\"name\":\"Inventiones mathematicae\",\"volume\":\"24 1\",\"pages\":\"\"},\"PeriodicalIF\":2.6000,\"publicationDate\":\"2024-04-03\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Inventiones mathematicae\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://doi.org/10.1007/s00222-024-01252-6\",\"RegionNum\":1,\"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":"Inventiones mathematicae","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1007/s00222-024-01252-6","RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
$\mathbf{C^{2}}$ -Lusin approximation of strongly convex functions
We prove that if \(u:\mathbb{R}^{n}\to \mathbb{R}\) is strongly convex, then for every \(\varepsilon >0\) there is a strongly convex function \(v\in C^{2}(\mathbb{R}^{n})\) such that \(|\{u\neq v\}|<\varepsilon \) and \(\Vert u-v\Vert _{\infty}<\varepsilon \).
期刊介绍:
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