{"title":"强可数维空间上的Lipschitz-free空间及其近似性质","authors":"Filip Talimdjioski","doi":"10.1112/blms.13200","DOIUrl":null,"url":null,"abstract":"<p>Let <span></span><math>\n <semantics>\n <mi>T</mi>\n <annotation>$T$</annotation>\n </semantics></math> be a compact, metrisable and strongly countable-dimensional topological space. Let <span></span><math>\n <semantics>\n <msup>\n <mi>M</mi>\n <mi>T</mi>\n </msup>\n <annotation>$\\mathcal {M}^T$</annotation>\n </semantics></math> be the set of all metrics <span></span><math>\n <semantics>\n <mi>d</mi>\n <annotation>$d$</annotation>\n </semantics></math> on <span></span><math>\n <semantics>\n <mi>T</mi>\n <annotation>$T$</annotation>\n </semantics></math> compatible with its topology, and equip <span></span><math>\n <semantics>\n <msup>\n <mi>M</mi>\n <mi>T</mi>\n </msup>\n <annotation>$\\mathcal {M}^T$</annotation>\n </semantics></math> with the topology of uniform convergence, where the metrics are regarded as functions on <span></span><math>\n <semantics>\n <msup>\n <mi>T</mi>\n <mn>2</mn>\n </msup>\n <annotation>$T^2$</annotation>\n </semantics></math>. We prove that the set <span></span><math>\n <semantics>\n <msup>\n <mi>A</mi>\n <mrow>\n <mi>T</mi>\n <mo>,</mo>\n <mn>1</mn>\n </mrow>\n </msup>\n <annotation>$\\mathcal {A}^{T,1}$</annotation>\n </semantics></math> of metrics <span></span><math>\n <semantics>\n <mrow>\n <mi>d</mi>\n <mo>∈</mo>\n <msup>\n <mi>M</mi>\n <mi>T</mi>\n </msup>\n </mrow>\n <annotation>$d\\in \\mathcal {M}^T$</annotation>\n </semantics></math> for which the Lipschitz-free space <span></span><math>\n <semantics>\n <mrow>\n <mi>F</mi>\n <mo>(</mo>\n <mi>T</mi>\n <mo>,</mo>\n <mi>d</mi>\n <mo>)</mo>\n </mrow>\n <annotation>$\\mathcal {F}(T,d)$</annotation>\n </semantics></math> has the metric approximation property is residual in <span></span><math>\n <semantics>\n <msup>\n <mi>M</mi>\n <mi>T</mi>\n </msup>\n <annotation>$\\mathcal {M}^T$</annotation>\n </semantics></math>.</p>","PeriodicalId":55298,"journal":{"name":"Bulletin of the London Mathematical Society","volume":"57 2","pages":"359-376"},"PeriodicalIF":0.9000,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1112/blms.13200","citationCount":"0","resultStr":"{\"title\":\"Lipschitz-free spaces over strongly countable-dimensional spaces and approximation properties\",\"authors\":\"Filip Talimdjioski\",\"doi\":\"10.1112/blms.13200\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>Let <span></span><math>\\n <semantics>\\n <mi>T</mi>\\n <annotation>$T$</annotation>\\n </semantics></math> be a compact, metrisable and strongly countable-dimensional topological space. Let <span></span><math>\\n <semantics>\\n <msup>\\n <mi>M</mi>\\n <mi>T</mi>\\n </msup>\\n <annotation>$\\\\mathcal {M}^T$</annotation>\\n </semantics></math> be the set of all metrics <span></span><math>\\n <semantics>\\n <mi>d</mi>\\n <annotation>$d$</annotation>\\n </semantics></math> on <span></span><math>\\n <semantics>\\n <mi>T</mi>\\n <annotation>$T$</annotation>\\n </semantics></math> compatible with its topology, and equip <span></span><math>\\n <semantics>\\n <msup>\\n <mi>M</mi>\\n <mi>T</mi>\\n </msup>\\n <annotation>$\\\\mathcal {M}^T$</annotation>\\n </semantics></math> with the topology of uniform convergence, where the metrics are regarded as functions on <span></span><math>\\n <semantics>\\n <msup>\\n <mi>T</mi>\\n <mn>2</mn>\\n </msup>\\n <annotation>$T^2$</annotation>\\n </semantics></math>. We prove that the set <span></span><math>\\n <semantics>\\n <msup>\\n <mi>A</mi>\\n <mrow>\\n <mi>T</mi>\\n <mo>,</mo>\\n <mn>1</mn>\\n </mrow>\\n </msup>\\n <annotation>$\\\\mathcal {A}^{T,1}$</annotation>\\n </semantics></math> of metrics <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>d</mi>\\n <mo>∈</mo>\\n <msup>\\n <mi>M</mi>\\n <mi>T</mi>\\n </msup>\\n </mrow>\\n <annotation>$d\\\\in \\\\mathcal {M}^T$</annotation>\\n </semantics></math> for which the Lipschitz-free space <span></span><math>\\n <semantics>\\n <mrow>\\n <mi>F</mi>\\n <mo>(</mo>\\n <mi>T</mi>\\n <mo>,</mo>\\n <mi>d</mi>\\n <mo>)</mo>\\n </mrow>\\n <annotation>$\\\\mathcal {F}(T,d)$</annotation>\\n </semantics></math> has the metric approximation property is residual in <span></span><math>\\n <semantics>\\n <msup>\\n <mi>M</mi>\\n <mi>T</mi>\\n </msup>\\n <annotation>$\\\\mathcal {M}^T$</annotation>\\n </semantics></math>.</p>\",\"PeriodicalId\":55298,\"journal\":{\"name\":\"Bulletin of the London Mathematical Society\",\"volume\":\"57 2\",\"pages\":\"359-376\"},\"PeriodicalIF\":0.9000,\"publicationDate\":\"2024-12-08\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1112/blms.13200\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Bulletin of the London Mathematical Society\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://londmathsoc.onlinelibrary.wiley.com/doi/10.1112/blms.13200\",\"RegionNum\":3,\"RegionCategory\":\"数学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"MATHEMATICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Bulletin of the London Mathematical Society","FirstCategoryId":"100","ListUrlMain":"https://londmathsoc.onlinelibrary.wiley.com/doi/10.1112/blms.13200","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
Lipschitz-free spaces over strongly countable-dimensional spaces and approximation properties
Let be a compact, metrisable and strongly countable-dimensional topological space. Let be the set of all metrics on compatible with its topology, and equip with the topology of uniform convergence, where the metrics are regarded as functions on . We prove that the set of metrics for which the Lipschitz-free space has the metric approximation property is residual in .