{"title":"反转曲面的取向同胚","authors":"I. Kuznietsova, S. Maksymenko","doi":"10.15673/TMGC.V13I4.1953","DOIUrl":null,"url":null,"abstract":"\nLet $M$ be a connected compact orientable surface, $f:M\\to \\mathbb{R}$ be a Morse function, and $h:M\\to M$ be a diffeomorphism which preserves $f$ in the sense that $f\\circ h = f$. \nWe will show that if $h$ leaves invariant each regular component of each level set of $f$ and reverses its orientation, then $h^2$ is isotopic to the identity map of $M$ via $f$-preserving isotopy. \nThis statement can be regarded as a foliated and a homotopy analogue of a well known observation that every reversing orientation orthogonal isomorphism of a plane has order $2$, i.e. a mirror symmetry with respect to some line. \nThe obtained results hold in fact for a larger class of maps with isolated singularities from compact orientable surfaces to the real line and the circle. \n \n ","PeriodicalId":36547,"journal":{"name":"Proceedings of the International Geometry Center","volume":"171 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2021-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":"{\"title\":\"Reversing orientation homeomorphisms of surfaces\",\"authors\":\"I. Kuznietsova, S. Maksymenko\",\"doi\":\"10.15673/TMGC.V13I4.1953\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"\\nLet $M$ be a connected compact orientable surface, $f:M\\\\to \\\\mathbb{R}$ be a Morse function, and $h:M\\\\to M$ be a diffeomorphism which preserves $f$ in the sense that $f\\\\circ h = f$. \\nWe will show that if $h$ leaves invariant each regular component of each level set of $f$ and reverses its orientation, then $h^2$ is isotopic to the identity map of $M$ via $f$-preserving isotopy. \\nThis statement can be regarded as a foliated and a homotopy analogue of a well known observation that every reversing orientation orthogonal isomorphism of a plane has order $2$, i.e. a mirror symmetry with respect to some line. \\nThe obtained results hold in fact for a larger class of maps with isolated singularities from compact orientable surfaces to the real line and the circle. \\n \\n \",\"PeriodicalId\":36547,\"journal\":{\"name\":\"Proceedings of the International Geometry Center\",\"volume\":\"171 1\",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2021-02-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"3\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Proceedings of the International Geometry Center\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.15673/TMGC.V13I4.1953\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"Mathematics\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the International Geometry Center","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.15673/TMGC.V13I4.1953","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"Mathematics","Score":null,"Total":0}
引用次数: 3
摘要
设$M$是一个连通紧致可定向曲面,$f:M\到\mathbb{R}$是一个莫尔斯函数,$h:M\到M$是一个在$f\circ h = f$的意义上保持$f$的微分同态。我们将证明,如果$h$使$f$的每个水平集的每个正则分量不变并反转其方向,则$h^2$是通过$f$保持同位素与$M$的恒等映射的同位素。这个命题可以看作是一个众所周知的观察的叶状和同伦的类比,即平面的每一个反转方向正交同构都有阶$2$,即关于某条线的镜像对称。所得结果实际上适用于从紧致可定向曲面到实线和圆的更大一类具有孤立奇点的映射。
Let $M$ be a connected compact orientable surface, $f:M\to \mathbb{R}$ be a Morse function, and $h:M\to M$ be a diffeomorphism which preserves $f$ in the sense that $f\circ h = f$.
We will show that if $h$ leaves invariant each regular component of each level set of $f$ and reverses its orientation, then $h^2$ is isotopic to the identity map of $M$ via $f$-preserving isotopy.
This statement can be regarded as a foliated and a homotopy analogue of a well known observation that every reversing orientation orthogonal isomorphism of a plane has order $2$, i.e. a mirror symmetry with respect to some line.
The obtained results hold in fact for a larger class of maps with isolated singularities from compact orientable surfaces to the real line and the circle.