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Related papers: Negative closed walks in signed graphs: A note

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We exhibit non-switching-isomorphic signed graphs that share a common underlying graph and common chromatic polynomials, thereby answering a question posed by Zaslavsky. For various joins of all-positive or all-negative signed complete…

Combinatorics · Mathematics 2024-07-02 Gary R. W. Greaves , Jeven Syatriadi , Charissa I. Utomo

A signed graph is an ordered pair $\Sigma=(G,\sigma),$ where $G=(V,E)$ is the underlying graph of $\Sigma$ with a signature function $\sigma:E\rightarrow \{1,-1\}$. In this article, we define $n^{th}$ power of a signed graph and discuss…

Combinatorics · Mathematics 2020-09-23 Shijin T , Germina K A , Shahul Hameed K

We show that the method of counting closed walks in strongly regular graphs rules out no parameter sets other than those ruled out by the method of counting eigenvalue multiplicities.

Combinatorics · Mathematics 2012-05-08 Vasek Chvatal

Matrix-based centrality measures have enjoyed significant popularity in network analysis, in no small part due to our ability to rigorously analyze their behavior as parameters vary. Recent work has considered the relationship between…

Social and Information Networks · Computer Science 2019-02-06 Eric Horton , Kyle Kloster , Blair D. Sullivan

Entropies based on walks on graphs and on their line-graphs are defined. They are based on the summation over diagonal and off-diagonal elements of the thermal Green's function of a graph also known as the communicability. The walk…

Mathematical Physics · Physics 2013-07-03 Ernesto Estrada , Jose A. de la Pena , Naomichi Hatano

We determine which bipartite graphs embedded in a torus are move-reduced. In addition, we classify equivalence classes of such move-reduced graphs under square/spider moves. This extends the class of minimal graphs on a torus studied by…

Combinatorics · Mathematics 2022-12-27 Pavel Galashin , Terrence George

A signed graph is a graph where the edges are assigned labels of either "$+$" or "$-$". The sign of a cycle in the graph is the product of the signs of its edges. We equip each signed complete graph with a vector whose entries are the…

Combinatorics · Mathematics 2017-07-03 Alex Schaefer

In a signed graph, each link is labeled with either a positive or a negative sign. This is particularly appropriate to model polarized systems. Such a graph can be characterized through the notion of structural balance, which relies on the…

Social and Information Networks · Computer Science 2019-05-01 Nejat Arinik , Rosa Figueiredo , Vincent Labatut

We consider homomorphisms of signed graphs from a computational perspective. In particular, we study the list homomorphism problem seeking a homomorphism of an input signed graph $(G,\sigma)$, equipped with lists $L(v) \subseteq V(H), v \in…

Combinatorics · Mathematics 2023-05-30 Jan Bok , Richard Brewster , Tomás Feder , Pavol Hell , Nikola Jedličková

We describe parity labelings of signed graphs; equivalently, cuts of the underlying graph that have nearly equal sides. We characterize the balanced signed graphs which are parity signed graphs. We give structural characterizations of all…

Combinatorics · Mathematics 2021-08-03 Mukti Acharya , Joseph Varghese Kureethara , Thomas Zaslavsky

Using spectral graph theory, we show how to obtain inequalities for the number of walks in graphs from nonnegative polynomials and present a new family of such inequalities.

Discrete Mathematics · Computer Science 2023-03-28 Nadja Willenborg , Sven Kosub

Topological relations between three degree-based invariants of a connected graph G are investigated. We present novel inequalities including M1(G), M2(G) and F(G), and show that in all cases equality holds if G is a regular or a semiregular…

Combinatorics · Mathematics 2015-09-29 Tamás Réti , Imre Felde

A graph $H$ is said to be positive if the homomorphism density $t_H(G)$ is non-negative for all weighted graphs $G$. The positive graph conjecture proposes a characterisation of such graphs, saying that a graph is positive if and only if it…

Combinatorics · Mathematics 2024-04-29 David Conlon , Joonkyung Lee , Leo Versteegen

The Grover walk is one of the most well-studied quantum walks on graphs. In this paper, we investigate its periodicity to reveal the relationship between the quantum walk and the underlying graph, focusing particularly on the…

Quantum Physics · Physics 2022-12-01 Yusuke Yoshie

The negative type inequalities of a metric space are closely tied to embeddability. A result by Gupta, Newman, and Rabinovich implies that if a metric graph $G$ does not contain a theta submetric as an embedding, then $G$ has negative type.…

Combinatorics · Mathematics 2025-01-27 Rutger Campbell , Kevin Hendrey , Ben Lund , Casey Tompkins

Signed shifts are generalizations of the shift map in which, interpreted as a map from the unit interval to itself sending x to the fractional part of Nx, some slopes are allowed to be negative. Permutations realized by the relative order…

Combinatorics · Mathematics 2019-01-03 Sergi Elizalde , Katherine Moore

Suppose that $\Gamma=(G, \sigma)$ is a connected signed graph with at least one cycle. The number of positive, negative and zero eigenvalues of the adjacency matrix of $\Gamma$ are called positive inertia index, negative inertia index and…

Spectral Theory · Mathematics 2025-05-14 Beiyan Liu , Fang Duan

We propose the total staggered quantum walk model and the total tessellation cover of a graph. This model uses the concept of total tessellation cover to describe the motion of the walker who is allowed to hop both to vertices and edges of…

Discrete Mathematics · Computer Science 2020-02-24 Alexandre Abreu , Luís Cunha , Celina de Figueiredo , Franklin Marquezino , Daniel Posner , Renato Portugal

The set D of distinct signed degrees of the vertices in a signed graph G is called its signed degree set. In this paper, we prove that every non-empty set of positive (negative) integers is the signed degree set of some connected signed…

Combinatorics · Mathematics 2007-05-23 S. Pirzada , T. A. Naikoo , F. A. Dar

The 1-2-3 Conjecture, introduced by Karo\'nski, {\L}uczak, and Thomason in 2004, was recently solved by Keusch. This implies that, for any connected graph $G$ different from $K_2$, we can turn $G$ into a locally irregular multigraph $M(G)$,…

Discrete Mathematics · Computer Science 2025-06-27 Julien Bensmail , Romain Bourneuf , Paul Colinot , Samuel Humeau , Timothée Martinod