arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2407.09306math.CVmath.AG
收藏

关于全纯叶层代数重数的拓扑不变性

On the topological invariance of the algebraic multiplicity of holomorphic foliations

Leonardo M. Câmara, Fernando Reis, José Edson Sampaio

AI总结:

本文研究全纯叶层代数重数的拓扑不变性,证明二维下重数为1是拓扑不变量并推广至高维,验证多类叶层的不变性,还修正了Rosas-Bazan的相关结论。

摘要:

本文研究叶层与常微分方程理论中最基础、最核心的问题之一:全纯叶层代数重数的拓扑不变性。我们首先证明了适用于叶层的A'Campo-Lê定理版本,即在二维情形下,代数重数等于1是一个拓扑不变量。该结果在温和条件下被进一步推广到高维,由此我们证明了鞍结点是拓扑不变的。我们还证实,在包含广义曲线、第二类叶层等在内的多类叶层中,代数重数均为拓扑不变量。此外,我们探讨了Rosas-Bazan提出的一项基本结论:若存在同胚可延拓过首次吹胀的例外除子的邻域,则代数重数具有拓扑不变性。我们证明,即便同胚无法延拓至整个除子,只要其能在奇点附近局部延拓,该结论依然成立。

英文摘要:

In this paper, we address one of the most basic and fundamental problems in the theory of foliations and ODEs, the topological invariance of the algebraic multiplicity of a holomorphic foliation. For instance, we prove an adapted version of A'Campo-Lê's Theorem for foliations, i.e., the algebraic multiplicity equal to one is a topological invariant in dimension two. This result is further generalized to higher dimensions under mild conditions; as a consequence, we prove that saddle-nodes are topologically invariant. We prove that the algebraic multiplicity is a topological invariant in several classes of foliations that contain, for instance, the generalized curves and the foliations of second type. Additionally, we address a fundamental result by Rosas-Bazan, which states that the existence of a homeomorphism extending through a neighborhood of the exceptional divisor of the first blow-up implies the topological invariance of the algebraic multiplicity. We show that the result holds if the homeomorphism extends locally near a singularity, even if it does not extend over the entire divisor.

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。

↑