{"title":"Hereditary Saturated Subsets and the Invariant Basis Number Property of the Leavitt Path Algebra of Cartesian Products","authors":"Min Li, Huanhuan Li, Yuquan Wen","doi":"10.1134/s0001434624030295","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p> In this note, first, we describe the (minimal) hereditary saturated subsets of finite acyclic graphs and finite graphs whose cycles have no exits. Then we show that the Cartesian product <span>\\(C_m\\times L_n\\)</span> of an <span>\\(m\\)</span>-cycle <span>\\(C_m\\)</span> by an <span>\\(n\\)</span>-line <span>\\(L_n\\)</span> has nontrivial hereditary saturated subsets even though the graphs <span>\\(C_m\\)</span> and <span>\\(L_n\\)</span> themselves have only trivial hereditary saturated subsets. Tomforde (Theorem 5.7 in “Uniqueness theorems and ideal structure for Leavitt path algebras,” J. Algebra <b>318</b> (2007), 270–299) proved that there exists a one-to-one correspondence between the set of graded ideals of the Leavitt path algebra <span>\\(L(E)\\)</span> of a graph <span>\\(E\\)</span> and the set of hereditary saturated subsets of <span>\\(E^0\\)</span>. This shows that the algebraic structure of the Leavitt path algebra <span>\\(L(C_m\\times L_n)\\)</span> of the Cartesian product is plentiful. We also prove that the invariant basis number property of <span>\\(L(C_m\\times L_n)\\)</span> can be derived from that of <span>\\(L(C_m)\\)</span>. More generally, we also show that the invariant basis number property of <span>\\(L(E\\times L_n)\\)</span> can be derived from that of <span>\\(L(E)\\)</span> if <span>\\(E\\)</span> is a finite graph without sinks. </p>","PeriodicalId":18294,"journal":{"name":"Mathematical Notes","volume":"47 4 1","pages":""},"PeriodicalIF":0.6000,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Mathematical Notes","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1134/s0001434624030295","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
In this note, first, we describe the (minimal) hereditary saturated subsets of finite acyclic graphs and finite graphs whose cycles have no exits. Then we show that the Cartesian product \(C_m\times L_n\) of an \(m\)-cycle \(C_m\) by an \(n\)-line \(L_n\) has nontrivial hereditary saturated subsets even though the graphs \(C_m\) and \(L_n\) themselves have only trivial hereditary saturated subsets. Tomforde (Theorem 5.7 in “Uniqueness theorems and ideal structure for Leavitt path algebras,” J. Algebra 318 (2007), 270–299) proved that there exists a one-to-one correspondence between the set of graded ideals of the Leavitt path algebra \(L(E)\) of a graph \(E\) and the set of hereditary saturated subsets of \(E^0\). This shows that the algebraic structure of the Leavitt path algebra \(L(C_m\times L_n)\) of the Cartesian product is plentiful. We also prove that the invariant basis number property of \(L(C_m\times L_n)\) can be derived from that of \(L(C_m)\). More generally, we also show that the invariant basis number property of \(L(E\times L_n)\) can be derived from that of \(L(E)\) if \(E\) is a finite graph without sinks.
期刊介绍:
Mathematical Notes is a journal that publishes research papers and review articles in modern algebra, geometry and number theory, functional analysis, logic, set and measure theory, topology, probability and stochastics, differential and noncommutative geometry, operator and group theory, asymptotic and approximation methods, mathematical finance, linear and nonlinear equations, ergodic and spectral theory, operator algebras, and other related theoretical fields. It also presents rigorous results in mathematical physics.