{"title":"Linear actions of","authors":"Jim Fowler, Courtney Thatcher","doi":"10.1017/prm.2024.36","DOIUrl":null,"url":null,"abstract":"<p>For an odd prime <span><span><span data-mathjax-type=\"texmath\"><span>$p$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline3.png\"/></span></span>, we consider free actions of <span><span><span data-mathjax-type=\"texmath\"><span>$(\\mathbb {Z}_{/{p}})^2$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline4.png\"/></span></span> on <span><span><span data-mathjax-type=\"texmath\"><span>$S^{2n-1}\\times S^{2n-1}$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline5.png\"/></span></span> given by linear actions of <span><span><span data-mathjax-type=\"texmath\"><span>$(\\mathbb {Z}_{/{p}})^2$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline6.png\"/></span></span> on <span><span><span data-mathjax-type=\"texmath\"><span>$\\mathbb {R}^{4n}$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline7.png\"/></span></span>. Simple examples include a lens space cross a lens space, but <span><span><span data-mathjax-type=\"texmath\"><span>$k$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline8.png\"/></span></span>-invariant calculations show that other quotients exist. Using the tools of Postnikov towers and surgery theory, the quotients are classified up to homotopy by the <span><span><span data-mathjax-type=\"texmath\"><span>$k$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline9.png\"/></span></span>-invariants and up to homeomorphism by the Pontrjagin classes. We will present these results and demonstrate how to calculate the <span><span><span data-mathjax-type=\"texmath\"><span>$k$</span></span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240416053638415-0645:S0308210524000362:S0308210524000362_inline10.png\"/></span></span>-invariants and the Pontrjagin classes from the rotation numbers.</p>","PeriodicalId":54560,"journal":{"name":"Proceedings of the Royal Society of Edinburgh Section A-Mathematics","volume":"51 1","pages":""},"PeriodicalIF":1.3000,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the Royal Society of Edinburgh Section A-Mathematics","FirstCategoryId":"100","ListUrlMain":"https://doi.org/10.1017/prm.2024.36","RegionNum":3,"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
For an odd prime $p$, we consider free actions of $(\mathbb {Z}_{/{p}})^2$ on $S^{2n-1}\times S^{2n-1}$ given by linear actions of $(\mathbb {Z}_{/{p}})^2$ on $\mathbb {R}^{4n}$. Simple examples include a lens space cross a lens space, but $k$-invariant calculations show that other quotients exist. Using the tools of Postnikov towers and surgery theory, the quotients are classified up to homotopy by the $k$-invariants and up to homeomorphism by the Pontrjagin classes. We will present these results and demonstrate how to calculate the $k$-invariants and the Pontrjagin classes from the rotation numbers.
期刊介绍:
A flagship publication of The Royal Society of Edinburgh, Proceedings A is a prestigious, general mathematics journal publishing peer-reviewed papers of international standard across the whole spectrum of mathematics, but with the emphasis on applied analysis and differential equations.
An international journal, publishing six issues per year, Proceedings A has been publishing the highest-quality mathematical research since 1884. Recent issues have included a wealth of key contributors and considered research papers.