{"title":"不严格的点式吸引子","authors":"Magdalena Nowak","doi":"10.1016/j.indag.2023.10.002","DOIUrl":null,"url":null,"abstract":"<div><p>We deal with the finite family <span><math><mi>F</mi></math></span><span> of continuous maps on the Hausdorff space </span><span><math><mi>X</mi></math></span><span>. A nonempty compact subset </span><span><math><mi>A</mi></math></span><span> of such space is called a strict attractor if it has an open neighborhood </span><span><math><mi>U</mi></math></span> such that <span><math><mrow><mi>A</mi><mo>=</mo><msub><mrow><mo>lim</mo></mrow><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></msub><msup><mrow><mi>F</mi></mrow><mrow><mi>n</mi></mrow></msup><mrow><mo>(</mo><mi>S</mi><mo>)</mo></mrow></mrow></math></span> for every nonempty compact <span><math><mrow><mi>S</mi><mo>⊂</mo><mi>U</mi></mrow></math></span><span>. Every strict attractor is a pointwise attractor, which means that the set </span><span><math><mrow><mo>{</mo><mi>x</mi><mo>∈</mo><mi>X</mi><mo>;</mo><msub><mrow><mo>lim</mo></mrow><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></msub><msup><mrow><mi>F</mi></mrow><mrow><mi>n</mi></mrow></msup><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>=</mo><mi>A</mi><mo>}</mo></mrow></math></span> contains <span><math><mi>A</mi></math></span> in its interior.</p><p>We present a class of examples of pointwise attractors – from the finite set to the Sierpiński carpet – which are not strict when we add to the system one nonexpansive map.</p></div>","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Pointwise attractors which are not strict\",\"authors\":\"Magdalena Nowak\",\"doi\":\"10.1016/j.indag.2023.10.002\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>We deal with the finite family <span><math><mi>F</mi></math></span><span> of continuous maps on the Hausdorff space </span><span><math><mi>X</mi></math></span><span>. A nonempty compact subset </span><span><math><mi>A</mi></math></span><span> of such space is called a strict attractor if it has an open neighborhood </span><span><math><mi>U</mi></math></span> such that <span><math><mrow><mi>A</mi><mo>=</mo><msub><mrow><mo>lim</mo></mrow><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></msub><msup><mrow><mi>F</mi></mrow><mrow><mi>n</mi></mrow></msup><mrow><mo>(</mo><mi>S</mi><mo>)</mo></mrow></mrow></math></span> for every nonempty compact <span><math><mrow><mi>S</mi><mo>⊂</mo><mi>U</mi></mrow></math></span><span>. Every strict attractor is a pointwise attractor, which means that the set </span><span><math><mrow><mo>{</mo><mi>x</mi><mo>∈</mo><mi>X</mi><mo>;</mo><msub><mrow><mo>lim</mo></mrow><mrow><mi>n</mi><mo>→</mo><mi>∞</mi></mrow></msub><msup><mrow><mi>F</mi></mrow><mrow><mi>n</mi></mrow></msup><mrow><mo>(</mo><mi>x</mi><mo>)</mo></mrow><mo>=</mo><mi>A</mi><mo>}</mo></mrow></math></span> contains <span><math><mi>A</mi></math></span> in its interior.</p><p>We present a class of examples of pointwise attractors – from the finite set to the Sierpiński carpet – which are not strict when we add to the system one nonexpansive map.</p></div>\",\"PeriodicalId\":0,\"journal\":{\"name\":\"\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0,\"publicationDate\":\"2024-01-01\",\"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/S0019357723000940\",\"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/S0019357723000940","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
我们处理的是豪斯多夫空间 X 上连续映射的有限族 F。如果该空间的非空紧凑子集 A 有一个开放邻域 U,使得对于每个非空紧凑 S⊂U,A=limn→∞Fn(S),则该子集称为严格吸引子。每个严格吸引子都是点式吸引子,这意味着集合{x∈X;limn→∞Fn(x)=A}的内部包含A。我们提出了一类点式吸引子的例子--从有限集到西尔潘斯基地毯--当我们在系统中加入一个非膨胀映射时,这些吸引子就不是严格的了。
We deal with the finite family of continuous maps on the Hausdorff space . A nonempty compact subset of such space is called a strict attractor if it has an open neighborhood such that for every nonempty compact . Every strict attractor is a pointwise attractor, which means that the set contains in its interior.
We present a class of examples of pointwise attractors – from the finite set to the Sierpiński carpet – which are not strict when we add to the system one nonexpansive map.