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arXiv 2103.00703math.GTmath.AT
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具有有限基本群的偶数维流形的极小欧拉示性数

Minimal Euler Characteristics for Even-Dimensional Manifolds with Finite Fundamental Group

Alejandro Adem, Ian Hambleton

摘要:

本文研究了具有$(n-1)$ -连通泛覆盖和$F_n$型基本群$G$的闭可定向拓扑$2n$ -流形的欧拉示性数$χ(M)$.我们定义$q_{2n}(G)$,一个广义版本的Hausmann-Weinberger不变量的4-流形,作为最小值的$(-1)^nχ(M)$。对于所有的$n\geq 2$,我们建立了一个加强和扩展版本的估计,在明确的上同调不变量的$G$。作为一个应用,我们得到了新的限制,非交换有限群产生的基本群的有理同调4-球面。

英文摘要:

We consider the Euler characteristics $χ(M)$ of closed orientable topological $2n$-manifolds with $(n-1)$-connected universal cover and a given fundamental group $G$ of type $F_n$. We define $q_{2n}(G)$, a generalized version of the Hausmann-Weinberger invariant for 4-manifolds, as the minimal value of $(-1)^nχ(M)$. For all $n\geq 2$, we establish a strengthened and extended version of their estimates, in terms of explicit cohomological invariants of $G$. As an application we obtain new restrictions for non-abelian finite groups arising as fundamental groups of rational homology 4-spheres.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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