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arXiv 2004.13793math.GT
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非退化局部驯服奇点上的分层Morse临界点与Brasselet数

Stratified Morse critical points and Brasselet number on non-degenerate locally tame singularities

Thaís M. Dalbelo, Hellen Santana

AI总结:

本文证明在非退化局部驯服完备交奇点族上,Brasselet数之差与Milnor纤维正则部分上Morse临界点数目相关,连接了拓扑与几何性质,并导出基于Newton多面体的公式。

摘要:

由Goresky和MacPherson提出的Morse理论的推广是一个里程碑,它彻底区分了奇异空间的拓扑研究与几何研究。设$\{X_t\}_t$是$\mathbb{C}^n$中完备交簇在$0$处的一个合适的芽族,$\{f_t\}_t, \{g_t\}_t$是定义在$X_t$上的非常值多项式函数族。如果对于每个$t$,芽$X_t$、$X_t \cap f_t^{-1}(0)$和$X_t\cap f_t^{-1}(0) \cap g_t^{-1}(0)$都是非退化的、局部驯服的完备交簇,我们证明Brasselet数${\rm B}_{f_t,X_t}(0)$与${\rm B}_{f_t,X_t\cap g_t^{-1}(0)}(0)$之差与$f_t$的Milnor纤维正则部分上在$g_t$的morse化中出现的Morse临界点的数目相关,即使在$g_t$的临界轨迹具有任意维数的情况下也是如此。这一结果将拓扑性质与几何性质联系起来,并使我们能够确定一些有趣的公式,这些公式主要涉及Newton多面体的组合信息。

英文摘要:

The generalization of the Morse theory presented by Goresky and MacPherson is a landmark that divided completely the topological and geo\-me\-tri\-cal study of singular spaces. Let \{$X_t\}_t$ be a suitable family of germs at $0$ of complete intersection varieties in $\mathbb{C}^n$ and $\{f_t\}_t, \{g_t\}_t$ families of non-constant polynomial functions on $X_t$. If the germs $X_t$, $X_t \cap f_t^{-1}(0)$ and $X_t\cap f_t^{-1}(0) \cap g_t^{-1}(0)$ are non-degenerate, locally tame, complete intersection varieties, for each $t,$ we prove that the difference of the Brasselet numbers, ${\rm B}_{f_t,X_t}(0)$ and ${\rm B}_{f_t,X_t\cap g_t^{-1}(0)}(0)$, is related with the number of Morse critical points {on the regular part of the Milnor fiber} of $f_t$ appearing in a morsefication of $g_t$, even in the case where $g_t$ has a critical locus with arbitrary dimension. This result connects topological and geometric properties and allows us to determine some interesting formulae, mainly in terms of the combinatorial information from Newton polyhedra.

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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