English
Related papers

Related papers: Connectivity versus Lin-Lu-Yau curvature

200 papers

An edge-colored graph $G$ is \emph{conflict-free connected} if any two of its vertices are connected by a path, which contains a color used on exactly one of its edges. The \emph{conflict-free connection number} of a connected graph $G$,…

Combinatorics · Mathematics 2018-05-09 Hong Chang , Trung Duy Doan , Zhong Huang , Stanislav Jendrol' , Xueliang Li , Ingo Schiermeyer

The connectivity is an important parameter to evaluate the robustness of a network. As a generalization, structure connectivity and substructure connectivity of graphs were proposed. For connected graphs $G$ and $H$, the $H$-structure…

Combinatorics · Mathematics 2022-11-23 Lina Ba , Hailun Wu , Heping Zhang

Let $G$ be a graph and $T$ a certain connected subgraph of $G$. The $T$-structure connectivity $\kappa(G; T)$ (or resp., $T$-substructure connectivity $\kappa^{s}(G; T)$) of $G$ is the minimum number of a set of subgraphs…

Combinatorics · Mathematics 2018-03-23 Dong Li , Xiaolan Hu , Huiqing Liu

In this paper, we derive Li-Yau inequality for unbounded Laplacian on complete weighted graphs with the assumption of the curvature-dimension inequality $CDE'(n,K)$, which can be regarded as a notion of curvature on graphs. Furthermore, we…

Differential Geometry · Mathematics 2018-01-25 Chao Gong , Yong Lin , Shuang Liu , Shing-Tung Yau

Let $G$ be a connected nonregular graphs of order $n$ with maximum degree $\Delta$ that attains the maximum spectral radius. Liu and Li (2008) proposed a conjecture stating that $G$ has a degree sequence $(\Delta,\ldots,\Delta,\delta)$ with…

Combinatorics · Mathematics 2024-11-27 Zejun Huang , Jiahui Liu , Chenxi Yang

We prove that a connected graph has linear rank-width 1 if and only if it is a distance-hereditary graph and its split decomposition tree is a path. An immediate consequence is that one can decide in linear time whether a graph has linear…

Discrete Mathematics · Computer Science 2014-07-09 Binh-Minh Bui-Xuan , Mamadou Moustapha Kanté , Vincent Limouzy

Multivariate graphs are prolific across many fields, including transportation and neuroscience. A key task in graph analysis is the exploration of connectivity, to, for example, analyze how signals flow through neurons, or to explore how…

In this paper, we study how the distance spectral radius behaves when the graph is perturbed by grafting edges. As applications, we also determine the graph with $k$ cut vertices (respectively, $k$ cut edges) with the minimal distance…

Spectral Theory · Mathematics 2010-11-10 Xiaoling Zhang , Chris Godsil

Fiber graphs of Gr\"obner bases from contingency tables are important in statistical hypothesis testing, where one studies random walks on these graphs using the Metropolis-Hastings algorithm. The connectivity of the graphs has implications…

Combinatorics · Mathematics 2013-10-29 Samu Potka

The generalized $k$-connectivity $\kappa_{k}(G)$ of a graph $G$ is a parameter that can measure the reliability of a network $G$ to connect any $k$ vertices in $G$, which is proved to be NP-complete for a general graph $G$. Let $S\subseteq…

Combinatorics · Mathematics 2018-08-31 Shu-Li Zhao , Rong-Xia Hao

We determine the minimum sum--connectivity index of bicyclic graphs with $n$ vertices and matching number $m$, where $2\le m\le \lfloor\frac{n}{2}\rfloor$, the minimum and the second minimum, as well as the maximum and the second maximum…

Combinatorics · Mathematics 2012-02-28 Zhibin Du , Bo Zhou

Complex systems of interacting components often can be modeled by a simple graph $\mathcal{G}$ that consists of a set of $n$ nodes and a set of $m$ edges. Such a graph can be represented by an adjacency matrix $A\in\R^{n\times n}$, whose…

Physics and Society · Physics 2025-09-17 Silvia Noschese , Lothar Reichel

The approach of quantifying the damage inflicted on a graph in Albert, Jeong and Barabsi's (AJB) report "Error and Attack Tolerance of Complex Networks" using the size of the largest connected component and the average size of the remaining…

Digital Libraries · Computer Science 2011-03-17 Charles L. Cartledge , Michael L. Nelson

The connection between curvature and topology is a very well-studied theme in the subject of differential geometry. By suitably defining curvature on networks, the study of this theme has been extended into the domain of network analysis as…

Social and Information Networks · Computer Science 2024-07-10 Sathyanarayanan Rengaswami , Theodora Bourni , Vasileios Maroulas

We say that a graph $G$ is $(2,m)$-linked if, for any distinct vertices $a_1,\ldots, a_m, b_1,b_2$ in $G$, there exist vertex disjoint connected subgraphs $A,B$ of $G$ such that $\{a_1, \ldots, a_m\}$ is contained in $A$ and $\{b_1,b_2\}$…

Combinatorics · Mathematics 2023-03-23 Xiying Du , Yanjia Li , Shijie Xie , Xingxing Yu

In recent years, discrete spaces such as graphs attract much attention as models for physical spacetime or as models for testing the spirit of non-commutative geometry. In this work, we construct the differential algebras for graphs by…

q-alg · Mathematics 2016-09-08 Sunggoo Cho , Kwang Sung Park

Token graphs, or symmetric powers of graphs, see \cite{alavi2002survey} and \cite{Fabila-Monroy2012}, are defined on the $k$-combinations of the vertex set of some graph $L$, where edges exist between two such combinations, if their…

Combinatorics · Mathematics 2023-07-14 Jens Walter Fischer

We present a method to control gonality of nonarchimedean curves based on graph theory. Let k denote a complete nonarchimedean valued field. We first prove a lower bound for the gonality of a curve over the algebraic closure of k in terms…

Algebraic Geometry · Mathematics 2013-12-12 Gunther Cornelissen , Fumiharu Kato , Janne Kool

For every $r \in \mathbb{N}$, let $\theta_r$ denote the graph with two vertices and $r$ parallel edges. The $\theta_r$-girth of a graph $G$ is the minimum number of edges of a subgraph of $G$ that can be contracted to $\theta_r$. This…

Combinatorics · Mathematics 2017-01-19 Dimitris Chatzidimitriou , Jean-Florent Raymond , Ignasi Sau , Dimitrios M. Thilikos

A connected graph $G$ is said to be $k$-connected if it has more than $k$ vertices and remains connected whenever fewer than $k$ vertices are deleted. In this paper, for a connected graph $G$ with sufficiently large order, we present a…

Combinatorics · Mathematics 2021-09-17 Peng-Li Zhang , Lihua Feng , Weijun Liu , Xiao-Dong Zhang