English
Related papers

Related papers: On the Isomorphism Problem for Helly Circular-Arc …

200 papers

We solve the isomorphism problem for the whole class of Lins-Mandel gems (graphs encoded manifolds). We also present certain homeomorphisms of branched cyclic coverings of two-bridge hyperbolic links. As a consequence, we prove that, in in…

Geometric Topology · Mathematics 2007-05-23 Sostenes Lins , Michele Mulazzani

Circle graphs are intersection graphs of chords of a circle. In this paper, we present a new algorithm for the circle graph isomorphism problem running in time $O((n+m)\alpha(n+m))$ where $n$ is the number of vertices, $m$ is the number of…

Data Structures and Algorithms · Computer Science 2019-08-27 Vít Kalisz , Pavel Klavík , Peter Zeman

We introduce the regularized integrals for decorated graphs on elliptic curves, which produces an almost holomorphic function on upper half plane. Then we give the graph version of holomorphic anomaly equation to study the anti-holomorphic…

Mathematical Physics · Physics 2024-08-05 Xiaoxiao Yang

The graph isomorphism (GI) problem is the computational problem of finding a permutation of vertices of a given graph $G_1$ that transforms $G_1$ to another given graph $G_2$ and preserves the adjacency. In this work, we propose a quantum…

Quantum Physics · Physics 2019-01-23 Xi Li , Hanwu Chen

The mod-p cohomology ring of a non-trivial finite p-group is an infinite dimensional, finitely presented graded unital algebra over the field with p elements, with generators in positive degrees. We describe an effective algorithm to test…

Rings and Algebras · Mathematics 2015-03-17 Bettina Eick , Simon King

We study the complexity of isomorphism problems for d-way arrays, or tensors, under natural actions by classical groups such as orthogonal, unitary, and symplectic groups. Such problems arise naturally in statistical data analysis and…

Computational Complexity · Computer Science 2024-08-13 Zhili Chen , Joshua A. Grochow , Youming Qiao , Gang Tang , Chuanqi Zhang

A graph homomorphism is a vertex map which carries edges from a source graph to edges in a target graph. The instances of the Weighted Maximum H-Colourable Subgraph problem (MAX H-COL) are edge-weighted graphs G and the objective is to find…

Discrete Mathematics · Computer Science 2009-11-18 Robert Engström , Tommy Färnqvist , Peter Jonsson , Johan Thapper

A homomorphism from a graph $G$ to a graph $H$ is an edge-preserving mapping from $V(G)$ to $V(H)$. For a fixed graph $H$, in the list homomorphism problem, denoted by LHom($H$), we are given a graph $G$, whose every vertex $v$ is equipped…

Computational Complexity · Computer Science 2022-02-04 Karolina Okrasa , Paweł Rzążewski

This paper deals with the problem of finding, for a given graph and a given natural number k, a subgraph of k nodes with a maximum number of edges. This problem is known as the k-cluster problem and it is NP-hard on general graphs as well…

Data Structures and Algorithms · Computer Science 2011-11-09 George B. Mertzios

In this paper, we present two main results. First, by only one conjecture (Conjecture 2.9) for recognizing a vertex symmetric graph, which is the hardest task for our problem, we construct an algorithm for finding an isomorphism between two…

Data Structures and Algorithms · Computer Science 2017-06-29 Caishi Fang

In the $(G,H)$-isomorphism game, a verifier interacts with two non-communicating players (called provers) by privately sending each of them a random vertex from either $G$ or $H$, whose aim is to convince the verifier that two graphs $G$…

Combinatorics · Mathematics 2020-04-24 Laura Mančinska , David E. Roberson , Antonios Varvitsiotis

We prove that the classification problem for graphs and several types of algebraic lattices (distributive, congruence and modular) up to isomorphism contains the classification problem for pairs of matrices up to simultaneous similarity.

Combinatorics · Mathematics 2020-08-03 Ruvim Lipyanski , Natalia Vanetik

We consider the complexity of the recognition problem for two families of combinatorial structures. A graph $G=(V,E)$ is said to be an intersection graph of lines in space if every $v\in V$ can be mapped to a straight line $\ell (v)$ in…

Computational Geometry · Computer Science 2024-06-26 Jean Cardinal

In this short note, we show two NP-completeness results regarding the \emph{simultaneous representation problem}, introduced by Lubiw and Jampani. The simultaneous representation problem for a given class of intersection graphs asks if some…

Discrete Mathematics · Computer Science 2018-11-29 Jan Bok , Nikola Jedličková

The paper gives a thorough introduction to spectra of digraphs via its Hermitian adjacency matrix. This matrix is indexed by the vertices of the digraph, and the entry corresponding to an arc from $x$ to $y$ is equal to the complex unity…

Combinatorics · Mathematics 2015-05-07 Krystal Guo , Bojan Mohar

We study a class of holomorphic matrix models. The integrals are taken over middle dimensional cycles in the space of complex square matrices. As the size of the matrices tends to infinity, the distribution of eigenvalues is given by a…

High Energy Physics - Theory · Physics 2009-11-10 Giovanni Felder , Roman Riser

In the context of distributed certification, the recognition of graph classes has started to be intensively studied. For instance, different results related to the recognition of planar, bounded tree-width and $H$-minor free graphs have…

Distributed, Parallel, and Cluster Computing · Computer Science 2023-09-12 Benjamín Jauregui , Pedro Montealegre , Diego Ramírez-Romero , Ivan Rapaport

We consider the isomorphism problem for hypergraphs taking as input two hypergraphs over the same set of vertices $V$ and a permutation group $\Gamma$ over domain $V$, and asking whether there is a permutation $\gamma \in \Gamma$ that…

Data Structures and Algorithms · Computer Science 2022-10-26 Daniel Neuen

The generic homomorphism problem, which asks whether an input graph $G$ admits a homomorphism into a fixed target graph $H$, has been widely studied in the literature. In this article, we provide a fine-grained complexity classification of…

Computational Complexity · Computer Science 2022-10-14 Robert Ganian , Thekla Hamm , Viktoriia Korchemna , Karolina Okrasa , Kirill Simonov

By applying simplification operations to categories of multigraphs, several natural graph operations are shown to demonstrate categorical issues. The replacement of an undirected edge with a directed cycle for digraphs admits both a left…

Category Theory · Mathematics 2024-03-21 Will Grilliette