{"title":"Coalgebraic formal curve spectra and spectral jet spaces","authors":"E. Peterson","doi":"10.2140/gt.2020.24.1","DOIUrl":"https://doi.org/10.2140/gt.2020.24.1","url":null,"abstract":"We import into homotopy theory the algebro-geometric construction of the cotangent space of a geometric point on a scheme. Specializing to the category of spectra local to a Morava $K$-theory of height $d$, we show that this can be used to produce a choice-free model of the determinantal sphere as well as an efficient Picard-graded cellular decomposition of $K(mathbb Z_p, d+1)$. Coupling these ideas to work of Westerland, we give a \"Snaith's theorem\" for the Iwasawa extension of the $K(d)$-local sphere.","PeriodicalId":55105,"journal":{"name":"Geometry & Topology","volume":"3 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2019-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82395175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Floer homology, group orderability, and taut\u0000foliations of hyperbolic 3–manifolds","authors":"N. Dunfield","doi":"10.2140/gt.2020.24.2075","DOIUrl":"https://doi.org/10.2140/gt.2020.24.2075","url":null,"abstract":"This paper explores the conjecture that the following are equivalent for rational homology 3-spheres: having left-orderable fundamental group, having non-minimal Heegaard Floer homology, and admitting a co-orientable taut foliation. In particular, it adds further evidence in favor of this conjecture by studying these three properties for more than 300,000 hyperbolic rational homology 3-spheres. New or much improved methods for studying each of these properties form the bulk of the paper, including a new combinatorial criterion, called a foliar orientation, for showing that a 3-manifold has a taut foliation.","PeriodicalId":55105,"journal":{"name":"Geometry & Topology","volume":"12 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2019-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76179233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}