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Related papers: Homotopy theory for digraphs

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In this paper we develop the theory of train track maps on graphs of groups. Expanding a definition of Bass, we define a notion of a map of a graph of groups, and of a homotopy equivalence. We prove that under one of two technical…

Group Theory · Mathematics 2022-11-15 Rylee Alanza Lyman

We define and study homotopy groups of cubical sets. To this end, we give four definitions of homotopy groups of a cubical set, prove that they are equivalent, and further that they agree with their topological analogues via the geometric…

Algebraic Topology · Mathematics 2025-12-23 Daniel Carranza , Chris Kapulkin

Lov\'asz (1967) showed that two graphs $G$ and $H$ are isomorphic if, and only if, they are homomorphism indistinguishable over all graphs, i.e., $G$ and $H$ admit the same number of number of homomorphisms from every graph $F$.…

Combinatorics · Mathematics 2026-01-27 Daniel Neuen , Tim Seppelt

This article deals with homomorphisms of oriented graphs with respect to push equivalence. Here homomorphisms refer to arc preserving vertex mappings, and push equivalence refers to the equivalence class of orientations of a graph $G$ those…

Combinatorics · Mathematics 2024-10-28 Tapas Das , Pavan P D , Sagnik Sen , S Taruni

We develop a theory of covering digraphs, similar to the theory of covering spaces. By applying this theory to Cayley digraphs, we build a "bridge" between GLMY-theory and group homology theory, which helps to reduce path homology…

Algebraic Topology · Mathematics 2024-04-02 Shaobo Di , Sergei O. Ivanov , Lev Mukoseev , Mengmeng Zhang

J. Przytycki has established a connection between the Hochschild homology of an algebra $A$ and the chromatic graph homology of a polygon graph with coefficients in $A$. In general the chromatic graph homology is not defined in the case…

Geometric Topology · Mathematics 2012-05-11 Paul Turner , Emmanuel Wagner

In this paper, we extend the definition of cohomology associated to monotone graph properties, to encompass twisted functor coefficients. We introduce oriented matchings on graphs, and focus on their (twisted) cohomology groups. We…

Combinatorics · Mathematics 2022-03-08 Luigi Caputi , Daniele Celoria , Carlo Collari

We consider constrained variants of graph homomorphisms such as embeddings, monomorphisms, full homomorphisms, surjective homomorpshims, and locally constrained homomorphisms. We also introduce a new variation on this theme which derives…

Combinatorics · Mathematics 2014-04-23 Yangjing Long

Homophily is a graph property describing the tendency of edges to connect similar nodes. There are several measures used for assessing homophily but all are known to have certain drawbacks: in particular, they cannot be reliably used for…

Machine Learning · Computer Science 2024-12-16 Mikhail Mironov , Liudmila Prokhorenkova

In this paper we introduce a path complex that can be regarded as a generalization of the notion of a simplicial complex. The main motivation for considering path complexes comes from directed graphs(digraphs). We obtain a new notion of the…

Combinatorics · Mathematics 2013-05-14 Alexander Grigor'yan , Yong Lin , Yuri Muranov , Shing-Tung Yau

This is a survey. The main subject of this survey is the homotopical or homological nature of certain structures which appear in classical problems about groups, Lie rings and group rings. It is well known that the (generalized) dimension…

Group Theory · Mathematics 2021-11-02 Roman Mikhailov

We present an algorithm to compute path homology for simple digraphs, and use it to topologically analyze various small digraphs en route to an analysis of complex temporal networks which exhibit such digraphs as underlying motifs. The…

Social and Information Networks · Computer Science 2021-01-15 Samir Chowdhury , Steve Huntsman , Matvey Yutin

We propose a novel method for topological analysis of unweighted graphs which is based on \textit{persistent homology}. The proposed method maps the input graph to a complete weighted graph where the weighting function maps each edge to a…

Algebraic Topology · Mathematics 2020-07-31 Padraig Corcoran

We study topological spaces with a distinguished set of paths, called directed paths. Since these directed paths are generally not reversible, the directed homotopy classes of directed paths do not assemble into a groupoid, and there is no…

Algebraic Topology · Mathematics 2021-01-29 Peter Bubenik

We extend the notion of 'homomorphism-homogeneity' to a wider class of kinds of maps than previously studied, and we investigate the relations between the resulting notions of homomorphism-homogeneity, giving several examples. We also give…

Combinatorics · Mathematics 2014-08-12 Deborah Lockett , John K. Truss

Homotopy type theory is a new branch of mathematics, based on a recently discovered connection between homotopy theory and type theory, which brings new ideas into the very foundation of mathematics. On the one hand, Voevodsky's subtle and…

Logic · Mathematics 2013-08-06 The Univalent Foundations Program

In proper homotopy theory, the original concept of point used in the classical homotopy theory of topological spaces is generalized in order to obtain homotopy groups that study the infinite of the spaces. This idea: "Using any arbitrary…

Algebraic Topology · Mathematics 2012-03-05 Francisco J. Díaz , José M. G. Calcines

We develop a robust foundation for studying the fundamental group(oid) in discrete homotopy theory, including: equivalent definitions and basic properties, the theory of covering graphs, and the discrete version of the Seifert-van Kampen…

Combinatorics · Mathematics 2025-12-23 Chris Kapulkin , Udit Mavinkurve

This paper studies a discrete homotopy theory for graphs introduced by Barcelo et al. We prove two main results. First we show that if $G$ is a graph containing no 3- or 4-cycles, then the $n$th discrete homotopy group $A_n(G)$ is trivial…

Combinatorics · Mathematics 2020-03-06 Bob Lutz

Homomorphically full graphs are those for which every homomorphic image is isomorphic to a subgraph. We extend the definition of homomorphically full to oriented graphs in two different ways. For the first of these, we show that…

Discrete Mathematics · Computer Science 2024-02-14 Thomas Bellitto , Christopher Duffy , Gary MacGillivray