{"title":"奇维流形差分同调的一些理性同调计算","authors":"Johannes Ebert, Jens Reinhold","doi":"10.1112/topo.12324","DOIUrl":null,"url":null,"abstract":"<p>We calculate the rational cohomology of the classifying space of the diffeomorphism group of the manifolds <math>\n <semantics>\n <mrow>\n <msubsup>\n <mi>U</mi>\n <mrow>\n <mi>g</mi>\n <mo>,</mo>\n <mn>1</mn>\n </mrow>\n <mi>n</mi>\n </msubsup>\n <mo>:</mo>\n <mo>=</mo>\n <msup>\n <mo>#</mo>\n <mi>g</mi>\n </msup>\n <mrow>\n <mo>(</mo>\n <msup>\n <mi>S</mi>\n <mi>n</mi>\n </msup>\n <mo>×</mo>\n <msup>\n <mi>S</mi>\n <mrow>\n <mi>n</mi>\n <mo>+</mo>\n <mn>1</mn>\n </mrow>\n </msup>\n <mo>)</mo>\n </mrow>\n <mo>∖</mo>\n <mi>int</mi>\n <mrow>\n <mo>(</mo>\n <msup>\n <mi>D</mi>\n <mrow>\n <mn>2</mn>\n <mi>n</mi>\n <mo>+</mo>\n <mn>1</mn>\n </mrow>\n </msup>\n <mo>)</mo>\n </mrow>\n </mrow>\n <annotation>$U_{g,1}^n:= \\#^g(S^n \\times S^{n+1})\\setminus \\mathrm{int}(D^{2n+1})$</annotation>\n </semantics></math>, for large <math>\n <semantics>\n <mi>g</mi>\n <annotation>$g$</annotation>\n </semantics></math> and <math>\n <semantics>\n <mi>n</mi>\n <annotation>$n$</annotation>\n </semantics></math>, up to degree <math>\n <semantics>\n <mrow>\n <mi>n</mi>\n <mo>−</mo>\n <mn>3</mn>\n </mrow>\n <annotation>$n-3$</annotation>\n </semantics></math>. The answer is that it is a free graded commutative algebra on an appropriate set of Miller–Morita–Mumford classes. Our proof goes through the classical three-step procedure: (a) compute the cohomology of the homotopy automorphisms, (b) use surgery to compare this to block diffeomorphisms, and (c) use pseudoisotopy theory and algebraic <math>\n <semantics>\n <mi>K</mi>\n <annotation>$K$</annotation>\n </semantics></math>-theory to get at actual diffeomorphism groups.</p>","PeriodicalId":0,"journal":{"name":"","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1112/topo.12324","citationCount":"0","resultStr":"{\"title\":\"Some rational homology computations for diffeomorphisms of odd-dimensional manifolds\",\"authors\":\"Johannes Ebert, Jens Reinhold\",\"doi\":\"10.1112/topo.12324\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p>We calculate the rational cohomology of the classifying space of the diffeomorphism group of the manifolds <math>\\n <semantics>\\n <mrow>\\n <msubsup>\\n <mi>U</mi>\\n <mrow>\\n <mi>g</mi>\\n <mo>,</mo>\\n <mn>1</mn>\\n </mrow>\\n <mi>n</mi>\\n </msubsup>\\n <mo>:</mo>\\n <mo>=</mo>\\n <msup>\\n <mo>#</mo>\\n <mi>g</mi>\\n </msup>\\n <mrow>\\n <mo>(</mo>\\n <msup>\\n <mi>S</mi>\\n <mi>n</mi>\\n </msup>\\n <mo>×</mo>\\n <msup>\\n <mi>S</mi>\\n <mrow>\\n <mi>n</mi>\\n <mo>+</mo>\\n <mn>1</mn>\\n </mrow>\\n </msup>\\n <mo>)</mo>\\n </mrow>\\n <mo>∖</mo>\\n <mi>int</mi>\\n <mrow>\\n <mo>(</mo>\\n <msup>\\n <mi>D</mi>\\n <mrow>\\n <mn>2</mn>\\n <mi>n</mi>\\n <mo>+</mo>\\n <mn>1</mn>\\n </mrow>\\n </msup>\\n <mo>)</mo>\\n </mrow>\\n </mrow>\\n <annotation>$U_{g,1}^n:= \\\\#^g(S^n \\\\times S^{n+1})\\\\setminus \\\\mathrm{int}(D^{2n+1})$</annotation>\\n </semantics></math>, for large <math>\\n <semantics>\\n <mi>g</mi>\\n <annotation>$g$</annotation>\\n </semantics></math> and <math>\\n <semantics>\\n <mi>n</mi>\\n <annotation>$n$</annotation>\\n </semantics></math>, up to degree <math>\\n <semantics>\\n <mrow>\\n <mi>n</mi>\\n <mo>−</mo>\\n <mn>3</mn>\\n </mrow>\\n <annotation>$n-3$</annotation>\\n </semantics></math>. The answer is that it is a free graded commutative algebra on an appropriate set of Miller–Morita–Mumford classes. Our proof goes through the classical three-step procedure: (a) compute the cohomology of the homotopy automorphisms, (b) use surgery to compare this to block diffeomorphisms, and (c) use pseudoisotopy theory and algebraic <math>\\n <semantics>\\n <mi>K</mi>\\n <annotation>$K$</annotation>\\n </semantics></math>-theory to get at actual diffeomorphism groups.</p>\",\"PeriodicalId\":0,\"journal\":{\"name\":\"\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0,\"publicationDate\":\"2024-01-31\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://onlinelibrary.wiley.com/doi/epdf/10.1112/topo.12324\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"\",\"FirstCategoryId\":\"100\",\"ListUrlMain\":\"https://onlinelibrary.wiley.com/doi/10.1112/topo.12324\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1112/topo.12324","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
我们计算流形差分群分类空间的有理同调 U g , 1 n : = # g ( S n × S n + 1 ) ∖ int ( D 2 n + 1 ) $U_{g,1}^n:= \#^g(S^n \times S^{n+1})\setminus \mathrm{int}(D^{2n+1})$,对于大g $g$和n $n$,直到度数n - 3 $n-3$。答案是,它是一个在适当的米勒-莫里塔-蒙福德类集合上的自由分级交换代数。我们的证明经历了经典的三步程序:(a) 计算同调自形体的同调;(b) 利用外科手术将其与块差形体进行比较;(c) 利用伪拟态理论和代数 K $K$ 理论得到实际的差形群。
Some rational homology computations for diffeomorphisms of odd-dimensional manifolds
We calculate the rational cohomology of the classifying space of the diffeomorphism group of the manifolds , for large and , up to degree . The answer is that it is a free graded commutative algebra on an appropriate set of Miller–Morita–Mumford classes. Our proof goes through the classical three-step procedure: (a) compute the cohomology of the homotopy automorphisms, (b) use surgery to compare this to block diffeomorphisms, and (c) use pseudoisotopy theory and algebraic -theory to get at actual diffeomorphism groups.