{"title":"Pregeometry over locally o-minimal structures and dimension","authors":"Masato Fujita","doi":"10.1002/malq.202200069","DOIUrl":null,"url":null,"abstract":"<p>We define a discrete closure operator for definably complete locally o-minimal structures <math>\n <semantics>\n <mi>M</mi>\n <annotation>$\\mathcal {M}$</annotation>\n </semantics></math>. The pair of the underlying set of <math>\n <semantics>\n <mi>M</mi>\n <annotation>$\\mathcal {M}$</annotation>\n </semantics></math> and the discrete closure operator forms a pregeometry. We define the rank of a definable set over a set of parameters using this fact and call it <math>\n <semantics>\n <mo>discl</mo>\n <annotation>$\\operatorname{discl}$</annotation>\n </semantics></math>-dimension. A definable set <i>X</i> is of dimension equal to the <math>\n <semantics>\n <mo>discl</mo>\n <annotation>$\\operatorname{discl}$</annotation>\n </semantics></math>-dimension of <i>X</i>. The structure <math>\n <semantics>\n <mi>M</mi>\n <annotation>$\\mathcal {M}$</annotation>\n </semantics></math> is simultaneously a first-order topological structure. The dimension rank of a set definable in the first-order topological structure <math>\n <semantics>\n <mi>M</mi>\n <annotation>$\\mathcal {M}$</annotation>\n </semantics></math> also coincides with its dimension.</p>","PeriodicalId":49864,"journal":{"name":"Mathematical Logic Quarterly","volume":"69 4","pages":"472-481"},"PeriodicalIF":0.4000,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mathematical Logic Quarterly","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1002/malq.202200069","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"LOGIC","Score":null,"Total":0}
引用次数: 0
Abstract
We define a discrete closure operator for definably complete locally o-minimal structures . The pair of the underlying set of and the discrete closure operator forms a pregeometry. We define the rank of a definable set over a set of parameters using this fact and call it -dimension. A definable set X is of dimension equal to the -dimension of X. The structure is simultaneously a first-order topological structure. The dimension rank of a set definable in the first-order topological structure also coincides with its dimension.
期刊介绍:
Mathematical Logic Quarterly publishes original contributions on mathematical logic and foundations of mathematics and related areas, such as general logic, model theory, recursion theory, set theory, proof theory and constructive mathematics, algebraic logic, nonstandard models, and logical aspects of theoretical computer science.