Roman V. Dribas, Andrew S. Golovnev, Nikolay A. Gusev
{"title":"弱Sard性质","authors":"Roman V. Dribas, Andrew S. Golovnev, Nikolay A. Gusev","doi":"10.1016/j.jmaa.2025.130022","DOIUrl":null,"url":null,"abstract":"<div><div>If <span><math><mi>f</mi><mo>:</mo><msup><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow><mrow><mn>2</mn></mrow></msup><mo>→</mo><mi>R</mi></math></span> is of class <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> then Sard's theorem implies that <em>f</em> has the following <em>relaxed Sard property</em>: the image under <em>f</em> of the Lebesgue measure restricted to the critical set of <em>f</em> is a singular measure. We show that for <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>1</mn><mo>,</mo><mi>α</mi></mrow></msup></math></span> functions with <span><math><mi>α</mi><mo><</mo><mn>1</mn></math></span> this property is strictly stronger than the <em>weak Sard property</em> introduced by Alberti, Bianchini and Crippa, while for any monotone continuous function these two properties are equivalent.</div><div>We also show that even in the one-dimensional setting Hölder regularity is not sufficient for the relaxed Sard property.</div></div>","PeriodicalId":50147,"journal":{"name":"Journal of Mathematical Analysis and Applications","volume":"555 1","pages":"Article 130022"},"PeriodicalIF":1.2000,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"On the weak Sard property\",\"authors\":\"Roman V. Dribas, Andrew S. Golovnev, Nikolay A. Gusev\",\"doi\":\"10.1016/j.jmaa.2025.130022\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>If <span><math><mi>f</mi><mo>:</mo><msup><mrow><mo>[</mo><mn>0</mn><mo>,</mo><mn>1</mn><mo>]</mo></mrow><mrow><mn>2</mn></mrow></msup><mo>→</mo><mi>R</mi></math></span> is of class <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> then Sard's theorem implies that <em>f</em> has the following <em>relaxed Sard property</em>: the image under <em>f</em> of the Lebesgue measure restricted to the critical set of <em>f</em> is a singular measure. We show that for <span><math><msup><mrow><mi>C</mi></mrow><mrow><mn>1</mn><mo>,</mo><mi>α</mi></mrow></msup></math></span> functions with <span><math><mi>α</mi><mo><</mo><mn>1</mn></math></span> this property is strictly stronger than the <em>weak Sard property</em> introduced by Alberti, Bianchini and Crippa, while for any monotone continuous function these two properties are equivalent.</div><div>We also show that even in the one-dimensional setting Hölder regularity is not sufficient for the relaxed Sard property.</div></div>\",\"PeriodicalId\":50147,\"journal\":{\"name\":\"Journal of Mathematical Analysis and Applications\",\"volume\":\"555 1\",\"pages\":\"Article 130022\"},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2025-09-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Mathematical Analysis and Applications\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022247X25008030\",\"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":"Journal of Mathematical Analysis and Applications","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022247X25008030","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
If is of class then Sard's theorem implies that f has the following relaxed Sard property: the image under f of the Lebesgue measure restricted to the critical set of f is a singular measure. We show that for functions with this property is strictly stronger than the weak Sard property introduced by Alberti, Bianchini and Crippa, while for any monotone continuous function these two properties are equivalent.
We also show that even in the one-dimensional setting Hölder regularity is not sufficient for the relaxed Sard property.
期刊介绍:
The Journal of Mathematical Analysis and Applications presents papers that treat mathematical analysis and its numerous applications. The journal emphasizes articles devoted to the mathematical treatment of questions arising in physics, chemistry, biology, and engineering, particularly those that stress analytical aspects and novel problems and their solutions.
Papers are sought which employ one or more of the following areas of classical analysis:
• Analytic number theory
• Functional analysis and operator theory
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