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Related papers: Combinatorial spectra of graphs

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The study of spectral graph determination is a fascinating area of research in spectral graph theory and algebraic combinatorics. This field focuses on examining the spectral characterization of various classes of graphs, developing methods…

Combinatorics · Mathematics 2025-04-14 Igal Sason , Noam Krupnik , Suleiman Hamud , Abraham Berman

The spectrum of the normalized graph Laplacian yields a very comprehensive set of invariants of a graph. In order to understand the information contained in those invariants better, we systematically investigate the behavior of this…

Combinatorics · Mathematics 2012-10-19 Anirban Banerjee , Jürgen Jost

In this article there are two main results. The first result gives a formula, in terms of a log resolution, for the graded pieces of the Hodge filtration on the cohomology of a unitary local system of rank one on the complement of an…

Algebraic Geometry · Mathematics 2008-09-27 Nero Budur

In this paper we will prove that there exists a covariant functor from the category of schemes to the category of graphs. This functor provides a combination between algebraic varieties and combinatorial graphs so that the invariants…

Algebraic Geometry · Mathematics 2009-07-06 Feng-Wen An

In this paper, we define a ternary graph operation which generalizes the construction of subdivision graph, $R-$graph, central graph. Also, it generalizes the construction of overlay graph (Marius Somodi \emph{et al.}, 2017), and…

Combinatorics · Mathematics 2019-08-13 R. Rajkumar , M. Gayathri

A graph $G$ is $k$-edge-Hamiltonian if any collection of vertex-disjoint paths with at most $k$ edges altogether belong to a Hamiltonian cycle in $G$. A graph $G$ is $k$-Hamiltonian if for all $S\subseteq V(G)$ with $|S|\le k$, the subgraph…

Combinatorics · Mathematics 2024-04-09 Yongtao Li , Yuejian Peng

In this article we consider combinatorial maps approach to graphs on surfaces, and how between them can be establish terminological uniformity in favor of combinatorial maps in way rotations are set as base structural elements and all other…

General Mathematics · Mathematics 2012-07-25 Dainis Zeps , Paulis Kikusts

Some years ago, the harmonic polynomial was introduced in order to understand better the harmonic topological index; for instance, it allows to obtain bounds of the harmonic index of the main products of graphs. Here, we obtain several…

Combinatorics · Mathematics 2023-02-06 Walter Carballosa , Juan E. Nápoles , J. M Rodríguez , Omar Rosario , J. M. Sigarreta

Graph theory provides fundamental concepts for many fields of science like statistical physics, network analysis and theoretical computer science. Here we give a pedagogical introduction to graph theory, divided into three sections. In the…

Disordered Systems and Neural Networks · Physics 2007-05-23 Alexander K. Hartmann , Martin Weigt

Characterizing graphs by their spectra is a fundamental and challenging problem in spectral graph theory, which has received considerable attention in recent years. A major unsolved conjecture in this area is Haemers' conjecture which…

Combinatorics · Mathematics 2024-10-04 Wei Wang , Wei Wang

Graphs can be associated with a matrix according to some rule and we can find the spectrum of a graph with respect to that matrix. Two graphs are cospectral if they have the same spectrum. Constructions of cospectral graphs help us…

Combinatorics · Mathematics 2020-06-02 Kate Lorenzen

We study a combinatorial model of the quantum scalar field with polynomial potential on a graph. In the first quantization formalism, the value of a Feynman graph is given by a sum over maps from the Feynman graph to the spacetime graph…

Mathematical Physics · Physics 2023-08-16 Ivan Contreras , Santosh Kandel , Pavel Mnev , Konstantin Wernli

We first develop a general framework for Laplace operators defined in terms of the combinatorial structure of a simplicial complex. This includes, among others, the graph Laplacian, the combinatorial Laplacian on simplicial complexes, the…

Algebraic Topology · Mathematics 2011-11-09 Danijela Horak , Jürgen Jost

Existing approaches to solving combinatorial optimization problems on graphs suffer from the need to engineer each problem algorithmically, with practical problems recurring in many instances. The practical side of theoretical computer…

Machine Learning · Computer Science 2020-07-15 Natalia Vesselinova , Rebecca Steinert , Daniel F. Perez-Ramirez , Magnus Boman

The aim of the present article is to give an overview of spectral theory on metric graphs guided by spectral geometry on discrete graphs and manifolds. We present the basic concept of metric graphs and natural Laplacians acting on it and…

Combinatorics · Mathematics 2008-02-15 Olaf Post

Highly-regular graphs can be regarded as a combinatorial generalization of distance-regular graphs. From this standpoint, we study combinatorial aspects of highly-regular graphs. As a result, we give the following three main results in this…

Combinatorics · Mathematics 2017-10-06 Taichi Kousaka

We generalize the notion of a coloring complex of a graph to linearized combinatorial Hopf monoids. We determine when a linearized combinatorial Hopf monoid has such a construction, and discover some inequalities that are satisfied by the…

Combinatorics · Mathematics 2022-10-11 Jacob White

We discuss algebraic and combinatorial aspects of the Hamiltonian normal form theory. The main objective is to describe the normal form near a singular point purely in terms of the original Hamiltonian, avoiding the normalization procedure.…

Dynamical Systems · Mathematics 2026-05-05 Dmitry Treschev

In this talk, we are concerned with the formulation and understanding of the combinatorics of time-ordered n-point functions in terms of the Hopf algebra of field operators. Mathematically, this problem can be formulated as one in…

Mathematical Physics · Physics 2018-01-24 Angela Mestre , Robert Oeckl

The deep interconnection between linear algebra and graph theory allows one to interpret classical matrix invariants through combinatorial structures. To each square matrix A over a commutative ring K, one can associate a weighted directed…

Combinatorics · Mathematics 2025-11-11 Sudip Bera