{"title":"特征值空间中具有断开曲线的非奇异平面映射的注入性","authors":"Marco Sabatini","doi":"10.12775/tmna.2022.073","DOIUrl":null,"url":null,"abstract":"Fessler and Gutierrez \\cite{Fe}, \\cite{Gu} proved that if a non-singular planar map has Jacobian matrix without eigenvalues in $(0,+\\infty)$, then it is injective. We prove that the same holds replacing $(0,+\\infty)$ with any unbounded curve disconnecting the upper (lower) complex half-plane. Additionally we prove that a Jacobian map $(P,Q)$ is injective if $\\partial P/\\partial x + \\partial Q/\\partial y$ is not a surjective function.","PeriodicalId":23130,"journal":{"name":"Topological Methods in Nonlinear Analysis","volume":"73 1","pages":"0"},"PeriodicalIF":0.7000,"publicationDate":"2023-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Injectivity of non-singular planar maps with disconnecting curves in the eigenvalues space\",\"authors\":\"Marco Sabatini\",\"doi\":\"10.12775/tmna.2022.073\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Fessler and Gutierrez \\\\cite{Fe}, \\\\cite{Gu} proved that if a non-singular planar map has Jacobian matrix without eigenvalues in $(0,+\\\\infty)$, then it is injective. We prove that the same holds replacing $(0,+\\\\infty)$ with any unbounded curve disconnecting the upper (lower) complex half-plane. Additionally we prove that a Jacobian map $(P,Q)$ is injective if $\\\\partial P/\\\\partial x + \\\\partial Q/\\\\partial y$ is not a surjective function.\",\"PeriodicalId\":23130,\"journal\":{\"name\":\"Topological Methods in Nonlinear Analysis\",\"volume\":\"73 1\",\"pages\":\"0\"},\"PeriodicalIF\":0.7000,\"publicationDate\":\"2023-09-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Topological Methods in Nonlinear Analysis\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.12775/tmna.2022.073\",\"RegionNum\":4,\"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":"Topological Methods in Nonlinear Analysis","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.12775/tmna.2022.073","RegionNum":4,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
摘要
Fessler和Gutierrez \cite{Fe}, \cite{Gu}证明了如果一个非奇异平面映射在$(0,+\infty)$中具有没有特征值的雅可比矩阵,则该映射是内射的。我们证明了用与上(下)复半平面分离的任意无界曲线代替$(0,+\infty)$成立。另外,我们证明了如果$\partial P/\partial x + \partial Q/\partial y$不是满射函数,则雅可比映射$(P,Q)$是内射。
Injectivity of non-singular planar maps with disconnecting curves in the eigenvalues space
Fessler and Gutierrez \cite{Fe}, \cite{Gu} proved that if a non-singular planar map has Jacobian matrix without eigenvalues in $(0,+\infty)$, then it is injective. We prove that the same holds replacing $(0,+\infty)$ with any unbounded curve disconnecting the upper (lower) complex half-plane. Additionally we prove that a Jacobian map $(P,Q)$ is injective if $\partial P/\partial x + \partial Q/\partial y$ is not a surjective function.
期刊介绍:
Topological Methods in Nonlinear Analysis (TMNA) publishes research and survey papers on a wide range of nonlinear analysis, giving preference to those that employ topological methods. Papers in topology that are of interest in the treatment of nonlinear problems may also be included.