中文
相关论文

相关论文: Graph switching, 2-ranks, and graphical Hadamard m…

200 篇论文

We consider continuous-time quantum walks on distance-regular graphs of small diameter. Using results about the existence of complex Hadamard matrices in association schemes, we determine which of these graphs have quantum walks that admit…

组合数学 · 数学 2014-03-12 Chris Godsil , Natalie Mullin , Aidan Roy

The topological (or graph) structures of real-world networks are known to be predictive of multiple dynamic properties of the networks. Conventionally, a graph structure is represented using an adjacency matrix or a set of hand-crafted…

社会与信息网络 · 计算机科学 2016-10-21 Cheng Li , Xiaoxiao Guo , Qiaozhu Mei

This paper represents a significant leap forward in the problem of enumerating vertex-transitive graphs. Recent breakthroughs on symmetry of Cayley (di)graphs show that almost all finite Cayley (di)graphs have the smallest possible…

组合数学 · 数学 2025-11-25 Yunsong Gan , Pablo Spiga , Binzhou Xia

This paper considers *-graphs in which all vertices have degree 4 or 6, and studies the question of calculating the genus of orientable 2-surfaces into which such graphs may be embedded. A *-graph is a graph endowed with a formal adjacency…

组合数学 · 数学 2012-12-27 Tyler Friesen , Vassily Manturov

Graphical models are commonly used to represent conditional dependence relationships between variables. There are multiple methods available for exploring them from high-dimensional data, but almost all of them rely on the assumption that…

机器学习 · 统计学 2020-04-22 Tianxi Li , Cheng Qian , Elizaveta Levina , Ji Zhu

The low energy expansion of Type II superstring amplitudes at genus one is organized in terms of modular graph functions associated with Feynman graphs of a conformal scalar field on the torus. In earlier work, surprising identities between…

高能物理 - 理论 · 物理学 2017-10-16 Eric D'Hoker , Justin Kaidi

For any positive integer $m$, the complete graph on $2^{2m}(2^m+2)$ vertices is decomposed into $2^m+1$ commuting strongly regular graphs, which give rise to a symmetric association scheme of class $2^{m+2}-2$. Furthermore, the…

组合数学 · 数学 2017-01-23 Hadi Kharaghani , Sara Sasani , Sho Suda

We generalize the concept of strong walk-regularity to directed graphs. We call a digraph strongly $\ell$-walk-regular with $\ell >1$ if the number of walks of length $\ell$ from a vertex to another vertex depends only on whether the two…

组合数学 · 数学 2017-09-13 Edwin R. van Dam , Gholamreza Omidi

In 2015, Bogdanowicz gave a necessary and sufficient condition for a 4-regular circulant graph to be isomorphic to the Cartesian product of two cycles. Accordion graphs, denoted by $A[n,k]$, are 4-regular graphs on two parameters $n$ and…

组合数学 · 数学 2021-11-11 John Baptist Gauci , Jean Paul Zerafa

We compare three transitivity properties of finite graphs, namely, for a positive integer $s$, $s$-distance transitivity, $s$-geodesic transitivity and $s$-arc transitivity. It is known that if a finite graph is $s$-arc transitive but not…

组合数学 · 数学 2011-10-12 Alice Devillers , Wei Jin , Cai Heng Li , Cheryl E. Praeger

Large continuous-time Markov chains with exponentially small transition rates arise in modeling complex systems in physics, chemistry and biology. We propose a constructive graph-algorithmic approach to determine the sequence of critical…

概率论 · 数学 2017-02-01 Tingyue Gan , Maria Cameron

Despite several advances in recent years, learning causal structures represented by directed acyclic graphs (DAGs) remains a challenging task in high dimensional settings when the graphs to be learned are not sparse. In this paper, we…

机器学习 · 计算机科学 2023-05-16 Zhuangyan Fang , Shengyu Zhu , Jiji Zhang , Yue Liu , Zhitang Chen , Yangbo He

The authors studied in [Ann. Inst. Henri Poincar\'e D 9, 367-433, (2022)], a complex multi-matrix model with $\mathrm{U}(N)^2 \times \mathrm{O}(D)$ symmetry, and whose double scaling limit where simultaneously the large-$N$ and large-$D$…

数学物理 · 物理学 2024-11-28 Rémi Cocou Avohou , Reiko Toriumi , Matthias Vancraeynest

As an extension of the Four-Color Theorem it is conjectured that every planar graph of odd-girth at least $2k+1$ admits a homomorphism to $PC_{2k}=(\mathbb{Z}_2^{2k}, \{e_1, e_2, ...,e_{2k}, J\})$ where $e_i$'s are standard basis and $J$ is…

组合数学 · 数学 2015-01-22 Reza Naserasr , Sagnik Sen , Qiang Sun

The field of two-dimensional (2D) materials has expanded to multilayered systems where electronic, optical, and mechanical properties change-often dramatically-with stacking order, thickness, twist, and interlayer spacing [1-5]. For…

材料科学 · 物理学 2019-06-27 Suk Hyun Sung , Noah Schnitzer , Lola Brown , Jiwoong Park , Robert Hovden

A mixed dihedral group is a group $H$ with two disjoint subgroups $X$ and $Y$, each elementary abelian of order $2^n$, such that $H$ is generated by $X\cup Y$, and $H/H'\cong X\times Y$. In this paper, for each $n\geq 2$, we construct a…

组合数学 · 数学 2023-03-02 Daniel R. Hawtin , Jin-Xin Zhou , Cheryl E. Praeger

In this paper, some results concerning the colorings of graph powers are presented. The notion of helical graphs is introduced. We show that such graphs are hom-universal with respect to high odd-girth graphs whose $(2t+1)$st power is…

组合数学 · 数学 2008-03-31 Hossein Hajiabolhassan

Building upon [1], this study aims to introduce fractal geometry into graph theory, and to establish a potential theoretical foundation for complex networks. Specifically, we employ the method of substitution to create and explore…

动力系统 · 数学 2024-05-29 Nero Ziyu Li

The concept of domination in graphs plays a central role in understanding structural properties and applications in network theory. In this study, we focus on the paired disjunctive domination number in the context of middle graphs, a…

离散数学 · 计算机科学 2025-12-19 Hande Tuncel Golpek , Zeliha Kartal Yildiz , Aysun Aytac

A vertex subset S of a graph G is said to 2-dominate the graph if each vertex not in S has at least two neighbors in it. As usual, the associated parameter is the minimum cardinal of a 2-dominating set, which is called the 2-domination…