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We study topological properties of random closed curves on an orientable surface $S$ of negative Euler characteristic. Letting $\gamma_{n}$ denote the conjugacy class of the $n^{th}$ step of a simple random walk on the Cayley graph driven…

Geometric Topology · Mathematics 2022-11-17 Tarik Aougab , Jonah Gaster

Elek and Lippner (2010) showed that the convergence of a sequence of bounded-degree graphs implies the existence of a limit for the proportion of vertices covered by a maximum matching. We provide a characterization of the limiting…

Probability · Mathematics 2012-04-12 Charles Bordenave , Marc Lelarge , Justin Salez

We explore the possibility of using quantum walks on graphs to find structural anomalies, such as extra edges or loops, on a graph. We focus our attention on star graphs, whose edges are like spokes coming out of a central hub. If there are…

Quantum Physics · Physics 2015-05-19 Edgar Feldman , Mark Hillery , Hai-Woong Lee , Daniel Reitzner , Hongjun Zheng , Vladimir Buzek

We introduce a method to embed edge-colored graphs into families of expander graphs, which generalizes a framework developed by Dragani\'c, Krivelevich, and Nenadov (2022). As an application, we show that each family of sufficiently…

Combinatorics · Mathematics 2025-01-27 Ben Lund , Chuandong Xu

Given an edge-colored complete graph $K_n$ on $n$ vertices, a perfect (respectively, near-perfect) matching $M$ in $K_n$ with an even (respectively, odd) number of vertices is rainbow if all edges have distinct colors. In this paper, we…

Combinatorics · Mathematics 2020-12-14 Shuhei Saito , Wei Wu , Naoki Matsumoto

We consider the problem of detecting a community of densely connected vertices in a high-dimensional bipartite graph of size $n_1 \times n_2$. Under the null hypothesis, the observed graph is drawn from a bipartite Erd\H{o}s-Renyi…

Statistics Theory · Mathematics 2025-05-27 Julien Chhor , Parker Knight

Our main result is designing an algorithm that returns a vertex cover of $\mathcal{G}^\star$ with size at most $(3/2+\epsilon)$ times the expected size of the minimum vertex cover, using only $O(n/\epsilon p)$ non-adaptive queries. This…

Data Structures and Algorithms · Computer Science 2023-02-07 Mahsa Derakhshan , Naveen Durvasula , Nika Haghtalab

We give an upper bound on the number of perfect matchings in simple graphs with a given number of vertices and edges. We apply this result to give an upper bound on the number of 2-factors in a directed complete bipartite balanced graph on…

Combinatorics · Mathematics 2014-08-01 M. Aaghabali , S. Akbari , S. Friedland , K. Markstrom , Z. Tajfirouz

Given an $n\times n$ symmetric matrix $W\in [0,1]^{[n]\times [n]}$, let $\mathcal{G}(n,W)$ be the random graph obtained by independently including each edge $jk$ with probability $W_{jk}$. Given a degree sequence ${\bf d}=(d_1,\ldots,…

Combinatorics · Mathematics 2024-12-11 Pu Gao , Yuval Ohapkin

We prove that for any weakly convergent sequence of finite graphs with bounded vertex degrees, there exists a topological limit graphing.

Combinatorics · Mathematics 2007-05-23 Gabor Elek

This paper introduces an efficient quantum computing method for reducing special graphs in the context of the graph coloring problem. The special graphs considered include both symmetric and non-symmetric graphs where the axis passes…

Quantum Physics · Physics 2025-10-21 Lord Sen , Shyamapada Mukherjee

A graph G is uniquely K_r-saturated if it contains no clique with r vertices and if for all edges e in the complement, G + e has a unique clique with r vertices. Previously, few examples of uniquely K_r-saturated graphs were known, and…

Combinatorics · Mathematics 2012-03-07 Stephen G. Hartke , Derrick Stolee

A simple topological graph is a topological graph in which any two edges have at most one common point, which is either their common endpoint or a proper crossing. More generally, in a k-simple topological graph, every pair of edges has at…

Computational Geometry · Computer Science 2016-02-22 Péter Hajnal , Alexander Igamberdiev , Günter Rote , André Schulz

The aim of this work is to establish a linear instability criterium of stationary solutions for the Korteweg-de Vries model on a star graph with a structure represented by a finite collections of semi-infinite edges. By considering a…

Analysis of PDEs · Mathematics 2021-07-07 Jaime Angulo Pava , Márcio Cavalcante

We discuss formulations of boundary conditions in a quantum graph vertex and demonstrate that the so-called $ST$-form can be further reduced up to a form more effective in certain applications: In particular, in identifying the number of…

Quantum Physics · Physics 2010-11-22 Taksu Cheon , Pavel Exner , Ondrej Turek

We investigate the spectral properties of chaotic quantum graphs. We demonstrate that the `energy'--average over the spectrum of individual graphs can be traded for the functional average over a supersymmetric non--linear $\sigma$--model…

Chaotic Dynamics · Physics 2009-11-11 Sven Gnutzmann , Alexander Altland

In a random graph, counts for the number of vertices with given degrees will typically be dependent. We show via a multivariate normal and a Poisson process approximation that, for graphs which have independent edges, with a possibly…

Probability · Mathematics 2009-12-25 K. Lin , G. Reinert

A matching in a graph is uniquely restricted if no other matching covers exactly the same set of vertices. This notion was defined by Golumbic, Hirst, and Lewenstein and studied in a number of articles. Our contribution is twofold. We…

Combinatorics · Mathematics 2016-11-22 Julien Baste , Dieter Rautenbach , Ignasi Sau

We prove that if the number of edges does not exceed 7 then the asymptotics of eigenvalues of the Dirichlet problem uniquely determine the shape of the graph.

Mathematical Physics · Physics 2025-08-28 O. Boyko , D. Kaliuzhnyi-Verbovetskyi , V. Pivovarchik

We study a problem motivated by a question related to quantum-error-correcting codes. Combinatorially, it involves the following graph parameter: $$f(G)=\min\set{|A|+|\{x\in V\setminus A : d_A(x)\text{is odd}\}| : A\neq\emptyset},$$ where…

Combinatorics · Mathematics 2009-03-13 Tom Bohman , Andrzej Dudek , Alan Frieze , Oleg Pikhurko