arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2305.08086math.COmath.AT
收藏

关于离散 Morse 理论技术在不连通图复形上的一个应用的注记

A note on an application of discrete Morse theoretic techniques on the complex of disconnected graphs

Anupam Mondal, Pritam Chandra Pramanik

AI总结:

本文指出 Forman 在不连通图复形上构造离散梯度向量场时所用验证断言存在问题,给出反例,并用更具一般性的观察重新证明该向量场确为梯度场。

摘要:

Robin Forman 于 2002 年发表的极具影响力的论文《A User's Guide to Discrete Morse Theory》以非常易读的方式概述了这一主题。作为概念验证,作者利用本质上纯组合的离散 Morse 理论技术,确定了 n 阶不连通图的抽象单纯复形的拓扑结构(同伦型);此前 Victor Vassiliev 已使用经典拓扑方法完成了这项工作。这些技术包括在该复形上构造(并验证)一个离散梯度向量场。然而,其验证部分依赖于一个似乎并不成立的断言。在本注记中,我们针对这一特定断言给出了两个反例。我们还对更重要的断言——即所构造的离散向量场确实是梯度向量场——给出了另一种证明。我们的证明技术依赖于一个并非针对当前问题的关键观察,因此通常可用于验证一个构造出的离散向量场是否为梯度向量场。

英文摘要:

Robin Forman's highly influential 2002 paper A User's Guide to Discrete Morse Theory presents an overview of the subject in a very readable manner. As a proof of concept, the author determines the topology (homotopy type) of the abstract simplicial complex of disconnected graphs of order $n$ (which was previously done by Victor Vassiliev using classical topological methods) using discrete Morse theoretic techniques, which are purely combinatorial in nature. The techniques involve the construction (and verification) of a discrete gradient vector field on the complex. However, the verification part relies on a claim that doesn't seem to hold. In this note, we provide a couple of counterexamples against this specific claim. We also provide an alternative proof of the bigger claim that the constructed discrete vector field is indeed a gradient vector field. Our proof technique relies on a key observation which is not specific to the problem at hand, and thus is applicable while verifying a constructed discrete vector field is a gradient one in general.

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。

↑