{"title":"Sphere fibrations over highly connected manifolds","authors":"Samik Basu, Aloke Kr Ghosh","doi":"10.1112/jlms.70002","DOIUrl":null,"url":null,"abstract":"<p>We construct sphere fibrations over <span></span><math>\n <semantics>\n <mrow>\n <mo>(</mo>\n <mi>n</mi>\n <mo>−</mo>\n <mn>1</mn>\n <mo>)</mo>\n </mrow>\n <annotation>$(n-1)$</annotation>\n </semantics></math>-connected <span></span><math>\n <semantics>\n <mrow>\n <mn>2</mn>\n <mi>n</mi>\n </mrow>\n <annotation>$2n$</annotation>\n </semantics></math>-manifolds such that the total space is a connected sum of sphere products. More precisely, for <span></span><math>\n <semantics>\n <mi>n</mi>\n <annotation>$n$</annotation>\n </semantics></math> even, we construct fibrations <span></span><math>\n <semantics>\n <mrow>\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 <msup>\n <mo>#</mo>\n <mrow>\n <mi>k</mi>\n <mo>−</mo>\n <mn>1</mn>\n </mrow>\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 <mn>2</mn>\n <mi>n</mi>\n <mo>−</mo>\n <mn>1</mn>\n </mrow>\n </msup>\n <mo>)</mo>\n </mrow>\n <mo>→</mo>\n <msub>\n <mi>M</mi>\n <mi>k</mi>\n </msub>\n </mrow>\n <annotation>$S^{n-1} \\rightarrow \\#^{k-1}(S^n \\times S^{2n-1}) \\rightarrow M_k$</annotation>\n </semantics></math>, where <span></span><math>\n <semantics>\n <msub>\n <mi>M</mi>\n <mi>k</mi>\n </msub>\n <annotation>$M_k$</annotation>\n </semantics></math> is a <span></span><math>\n <semantics>\n <mrow>\n <mo>(</mo>\n <mi>n</mi>\n <mo>−</mo>\n <mn>1</mn>\n <mo>)</mo>\n </mrow>\n <annotation>$(n-1)$</annotation>\n </semantics></math>-connected <span></span><math>\n <semantics>\n <mrow>\n <mn>2</mn>\n <mi>n</mi>\n </mrow>\n <annotation>$2n$</annotation>\n </semantics></math>-dimensional Poincaré duality complex that satisfies <span></span><math>\n <semantics>\n <mrow>\n <msub>\n <mi>H</mi>\n <mi>n</mi>\n </msub>\n <mrow>\n <mo>(</mo>\n <msub>\n <mi>M</mi>\n <mi>k</mi>\n </msub>\n <mo>)</mo>\n </mrow>\n <mo>≅</mo>\n <msup>\n <mi>Z</mi>\n <mi>k</mi>\n </msup>\n </mrow>\n <annotation>$H_n(M_k)\\cong {\\mathbb {Z}}^k$</annotation>\n </semantics></math>, in a localised category of spaces. The construction of the fibration is proved for <span></span><math>\n <semantics>\n <mrow>\n <mi>k</mi>\n <mo>⩾</mo>\n <mn>2</mn>\n </mrow>\n <annotation>$k\\geqslant 2$</annotation>\n </semantics></math>, where the prime 2, and the primes that occur as torsion in <span></span><math>\n <semantics>\n <mrow>\n <msub>\n <mi>π</mi>\n <mrow>\n <mn>2</mn>\n <mi>n</mi>\n <mo>−</mo>\n <mn>1</mn>\n </mrow>\n </msub>\n <mrow>\n <mo>(</mo>\n <msup>\n <mi>S</mi>\n <mi>n</mi>\n </msup>\n <mo>)</mo>\n </mrow>\n </mrow>\n <annotation>$\\pi _{2n-1}(S^n)$</annotation>\n </semantics></math> are inverted. In specific cases, by either assuming <span></span><math>\n <semantics>\n <mi>n</mi>\n <annotation>$n$</annotation>\n </semantics></math> is small, or assuming <span></span><math>\n <semantics>\n <mi>k</mi>\n <annotation>$k$</annotation>\n </semantics></math> is large we can reduce the number of primes that need to be inverted. Integral results are obtained for <span></span><math>\n <semantics>\n <mrow>\n <mi>n</mi>\n <mo>=</mo>\n <mn>2</mn>\n </mrow>\n <annotation>$n=2$</annotation>\n </semantics></math> or 4, and if <span></span><math>\n <semantics>\n <mi>k</mi>\n <annotation>$k$</annotation>\n </semantics></math> is bigger than the number of cyclic summands in the stable stem <span></span><math>\n <semantics>\n <msubsup>\n <mi>π</mi>\n <mrow>\n <mi>n</mi>\n <mo>−</mo>\n <mn>1</mn>\n </mrow>\n <mi>s</mi>\n </msubsup>\n <annotation>$\\pi _{n-1}^s$</annotation>\n </semantics></math>, we obtain results after inverting 2. Finally, we prove some applications for fibrations over <span></span><math>\n <semantics>\n <mrow>\n <mi>N</mi>\n <mo>#</mo>\n <msub>\n <mi>M</mi>\n <mi>k</mi>\n </msub>\n </mrow>\n <annotation>$N\\# M_k$</annotation>\n </semantics></math>, and for looped configuration spaces.</p>","PeriodicalId":49989,"journal":{"name":"Journal of the London Mathematical Society-Second Series","volume":null,"pages":null},"PeriodicalIF":1.0000,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of the London Mathematical Society-Second Series","FirstCategoryId":"100","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1112/jlms.70002","RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
We construct sphere fibrations over -connected -manifolds such that the total space is a connected sum of sphere products. More precisely, for even, we construct fibrations , where is a -connected -dimensional Poincaré duality complex that satisfies , in a localised category of spaces. The construction of the fibration is proved for , where the prime 2, and the primes that occur as torsion in are inverted. In specific cases, by either assuming is small, or assuming is large we can reduce the number of primes that need to be inverted. Integral results are obtained for or 4, and if is bigger than the number of cyclic summands in the stable stem , we obtain results after inverting 2. Finally, we prove some applications for fibrations over , and for looped configuration spaces.
我们在 ( n - 1 ) $(n-1)$ 连通的 2 n $2n$ -manifold 上构建球体纤维,使得总空间是球体乘积的连通和。更确切地说,对于 n $n$ 偶数,我们构建了纤维 S n - 1 → # k - 1 ( S n × S 2 n - 1 ) → M k $S^{n-1} \rightarrow \#^{k-1}(S^n \times S^{2n-1}) \rightarrow M_k$ ,其中 M k $M_k$ 是一个 ( n - 1 ) $(n-1)$ 连接的 2 n $2n$ -dimensional Poincaré duality complex,满足 H n ( M k ) ≅ Z k $H_n(M_k)\cong {\mathbb {Z}}^k$ , 在一个局部化的空间类别中。在 k ⩾ 2 $k\geqslant 2$ 的情况下,证明了纤维的构造,其中素数 2 以及作为扭转出现在 π 2 n - 1 ( S n ) $\pi _{2n-1}(S^n)$ 中的素数都是反转的。在特定情况下,通过假设 n $n$ 较小或假设 k $k$ 较大,我们可以减少需要倒置的素数。对于 n = 2 $n=2$ 或 4,如果 k $k$ 大于稳定干π n - 1 s $p\i _{n-1}^s$中循环和的个数,我们就能得到反转 2 后的积分结果。最后,我们证明了在 N # M k $N\# M_k$ 上的纤化以及循环配置空间的一些应用。
期刊介绍:
The Journal of the London Mathematical Society has been publishing leading research in a broad range of mathematical subject areas since 1926. The Journal welcomes papers on subjects of general interest that represent a significant advance in mathematical knowledge, as well as submissions that are deemed to stimulate new interest and research activity.