Graphs and Combinatorics ( IF 0.6 ) Pub Date : 2021-06-15 , DOI: 10.1007/s00373-021-02333-6 Sinan G. Aksoy , Mark Kempton , Stephen J. Young
The universal cyclic edge-connectivity of a graph G is the least k such that there exists a set of k edges whose removal disconnects G into components where every component contains a cycle. We show that for graphs of minimum degree at least 3 and girth g at least 4, the universal cyclic edge-connectivity is bounded above by \((\Delta -2)g\) where \(\Delta \) is the maximum degree. We then prove that if the second eigenvalue of the adjacency matrix of a d-regular graph of girth \(g\ge 4\) is sufficiently small, then the universal cyclic edge-connectivity is \((d-2)g\), providing a spectral condition for when this upper bound on universal cyclic edge-connectivity is tight.
中文翻译:
极值循环边缘连接的频谱阈值
图G的通用循环边连通性是最小k,使得存在一组k 个边,这些边的移除将G断开为每个组件包含一个循环的组件。我们表明,对于最小度数至少为 3 且周长g至少为 4 的图,通用循环边连接性以\((\Delta -2)g\)为界,其中\(\Delta \)是最大度数. 然后我们证明,如果周长\(g\ge 4\)的d -正则图的邻接矩阵的第二个特征值足够小,那么通用循环边连通性是\((d-2)g\),当通用循环边连通性的这个上限很紧时,提供了一个频谱条件。