English
Related papers

Related papers: Spectral Gap of Random Hyperbolic Graphs and Relat…

200 papers

We study how the spectral gap of the normalized Laplacian of a random graph changes when an edge is added to or removed from the graph. There are known examples of graphs where, perhaps counterintuitively, adding an edge can decrease the…

Combinatorics · Mathematics 2015-06-23 Ronen Eldan , Miklós Rácz , Tselil Schramm

Laplacian Eigenvectors of the graph constructed from a data set are used in many spectral manifold learning algorithms such as diffusion maps and spectral clustering. Given a graph constructed from a random sample of a $d$-dimensional…

Machine Learning · Statistics 2015-10-29 Xu Wang

In this work, we study a family of random geometric graphs on hyperbolic spaces. In this setting, N points are chosen randomly on a hyperbolic space and any two of them are joined by an edge with probability that depends on their hyperbolic…

Combinatorics · Mathematics 2012-05-15 Nikolaos Fountoulakis

In this paper, we give tight bounds for the normalized Laplacian eigenvalues of hypergraphs that are not necessarily uniform, and provide an edge version interlacing theorem, a Cheeger inequality, and a discrepancy inequality that are…

Combinatorics · Mathematics 2025-04-15 Leyou Xu , Bo Zhou

We show that the diameter D(G_n) of a random labelled connected planar graph with n vertices is equal to n^{1/4+o(1)}, in probability. More precisely there exists a constant c>0 such that the probability that D(G_n) lies in the interval…

Combinatorics · Mathematics 2019-02-20 Guillaume Chapuy , Éric Fusy , Omer Giménez , Marc Noy

We study the problem of efficiently finding large common induced subgraphs of two independent Erd\H{o}s--R\'enyi random graphs $G_1, G_2 \sim \mathbb{G}(n,1/2)$. Recently, Chatterjee and Diaconis showed that the largest common induced…

Data Structures and Algorithms · Computer Science 2026-05-06 David Gamarnik , Miklós Z. Rácz , Gabe Schoenbach

How does the chromatic number of a graph chosen uniformly at random from all graphs on $n$ vertices behave? This quantity is a random variable, so one can ask (i) for upper and lower bounds on its typical values, and (ii) for bounds on how…

Combinatorics · Mathematics 2023-08-21 Annika Heckel , Oliver Riordan

Jiang, Tidor, Yao, Zhang, and Zhao recently showed that connected bounded degree graphs have sublinear second eigenvalue multiplicity (always referring to the adjacency matrix). This result was a key step in the solution to the problem of…

Combinatorics · Mathematics 2023-02-23 Milan Haiman , Carl Schildkraut , Shengtong Zhang , Yufei Zhao

We prove upper bounds on the graph diameters of polytopes in two settings. The first is a worst-case bound for polytopes defined by integer constraints in terms of the height of the integers and certain subdeterminants of the constraint…

Combinatorics · Mathematics 2022-09-16 Hariharan Narayanan , Rikhav Shah , Nikhil Srivastava

Bayesian network (BN) structure discovery algorithms typically either make assumptions about the sparsity of the true underlying network, or are limited by computational constraints to networks with a small number of variables. While these…

Machine Learning · Statistics 2023-07-14 Luke Duttweiler , Sally W. Thurston , Anthony Almudevar

We show that for every $n$-vertex graph with at least one edge, its treewidth is greater than or equal to $n \lambda_{2} / (\Delta + \lambda_{2}) - 1$, where $\Delta$ and $\lambda_{2}$ are the maximum degree and the second smallest…

Combinatorics · Mathematics 2024-04-15 Tatsuya Gima , Tesshu Hanaka , Kohei Noro , Hirotaka Ono , Yota Otachi

We study smooth linear spectral statistics of twisted Laplacians on random $n$-covers of a fixed compact hyperbolic surface $X$. We consider two aspects of such statistics. The first is the fluctuations of such statistics in a small energy…

Spectral Theory · Mathematics 2025-04-14 Yotam Maoz

It is known that, for an oriented hypergraph with (vertex) coloring number $\chi$ and smallest and largest normalized Laplacian eigenvalues $\lambda_1$ and $\lambda_N$, respectively, the inequality $\chi\geq…

Combinatorics · Mathematics 2026-02-23 Lies Beers , Raffaella Mulas

We study random walks on the giant component of Hyperbolic Random Graphs (HRGs), in the regime when the degree distribution obeys a power law with exponent in the range $(2,3)$. In particular, we first focus on the expected time for a…

Probability · Mathematics 2026-02-10 Marcos Kiwi , Markus Schepers , John Sylvester

We consider the bulk eigenvalue statistics of Laplacian matrices of large Erd\H{o}s-R\'enyi random graphs in the regime $p \geq N^{\delta}/N$ for any fixed $\delta >0$. We prove a local law down to the optimal scale $\eta \gtrsim N^{-1}$…

Probability · Mathematics 2015-10-22 Jiaoyang Huang , Benjamin Landon

For a graph $G$, the spectral radius $\lambda_{1}(G)$ of $G$ is the largest eigenvalue of its adjacency matrix. An odd wheel $W_{2k+1}$ with $k\geq2$ is a graph obtained from a cycle of order $2k$ by adding a new vertex connecting to all…

Combinatorics · Mathematics 2024-08-08 Wenqian Zhang

We study Linial-Meshulam random 2-complexes, which are two-dimensional analogues of Erd\H{o}s-R\'enyi random graphs. We find the threshold for simple connectivity to be p = n^{-1/2}. This is in contrast to the threshold for vanishing of the…

Combinatorics · Mathematics 2011-05-11 Eric Babson , Christopher Hoffman , Matthew Kahle

The Laplacian energy of a graph is the sum of the distances of the eigenvalues of the Laplacian matrix of the graph to the graph's average degree. The maximum Laplacian energy over all graphs on $n$ nodes and $m$ edges is conjectured to be…

Combinatorics · Mathematics 2017-04-05 Christoph Helmberg , Vilmar Trevisan

The difference between the two largest eigenvalues of the adjacency matrix of a graph $G$ is called the spectral gap of $G.$ If $G$ is a regular graph, then its spectral gap is equal to algebraic connectivity. Abdi, Ghorbani and Imrich, in…

Combinatorics · Mathematics 2022-12-06 Ruifang Liu , Jie Xue

We consider a model for complex networks that was recently proposed as a model for complex networks by Krioukov et al. In this model, nodes are chosen randomly inside a disk in the hyperbolic plane and two nodes are connected if they are at…

Probability · Mathematics 2026-01-14 Tobias Müller , Merlijn Staps