首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Finite domination, Novikov homology and nonsingular closed 1-forms
Authors:Dirk Schütz
Institution:1. Fachbereich Mathematik und Informatik, Westf?lische Wilhelms-Universit?t Münster, Einsteinstr. 62, 48149, Münster, Germany
Abstract:Let X be a finite connected CW-complex and ρ:MediaObjects/s00209-005-0868-8flb1.gif a regular covering space with free abelian covering transformation group. For ξ ∈ H1 (Xℝ) we define the notion of ξ-contractibility of X. This notion is closely related to the vanishing of the Novikov homology of the pair (X,ξ). We show that finite domination of MediaObjects/s00209-005-0868-8flb2.gif is equivalent to X being ξ-contractible for every nonzero ξ with ρ*ξ =0  ∈ H1(MediaObjects/s00209-005-0868-8flb2.gif; ℝ). If M is a closed connected smooth manifold the condition that M is ξ-contractible is necessary for the existence of a nonsingular closed 1-form representing ξ. Also ξ-contractibility guarantees the definition of the Latour obstruction τL(M,ξ) whose vanishing is then sufficient for the existence of a nonsingular closed 1-form provided  dim M≥6. Now if ρ:MediaObjects/s00209-005-0868-8flb3.gif is a finitely dominated regular ℤk-covering space we get that τL(M,ξ) is defined for every nonzero ξ with ρ*ξ=0 and the vanishing of one such obstruction implies the vanishing of all such τL(M,ξ).
Keywords:
本文献已被 SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号