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Related papers: Homotopy theory for digraphs

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Directed graphs have long been used to gain understanding of the structure of semigroups, and recently the structure of directed graph semigroups has been investigated resulting in a characterization theorem and an analog of Fruct's…

Combinatorics · Mathematics 2015-06-09 Tien Chih , Demitri Plessas

We propose a homology theory for locally compact spaces with ends in which the ends play a special role. The approach is motivated by results for graphs with ends, where it has been highly successful. But it was unclear how the original…

Algebraic Topology · Mathematics 2011-05-26 Reinhard Diestel , Philipp Sprüssel

We prove analogues of classical results for higher homotopy groups and singular homology groups of pseudotopological spaces. Pseudotopological spaces are a generalization of (\v{C}ech) closure spaces which are in turn a generalization of…

Algebraic Topology · Mathematics 2024-09-30 Nikola Milićević , Nicholas A. Scoville

Hypergraphs, as a generalization of simplicial complexes, have long been a subject of interest in their geometric interpretation. The subdivision of simplicial complexes can, to some extent, provide insights into the geometry of simplicial…

Algebraic Topology · Mathematics 2023-11-17 Jian Liu , Ran Liu , Jie Wu

Digraphs are generalizations of graphs in which each edge is assigned with a direction or two directions. In this paper, we define discrete Morse functions on digraphs, and prove that the homology of the Morse complex and the path homology…

Algebraic Topology · Mathematics 2020-07-28 Chong Wang , Shiquan Ren

Naturally occurring diagrams in algebraic topology are commutative up to homotopy, but not on the nose. It was quickly realized that very little can be done with this information. Homotopy coherent category theory arose out of a desire to…

Category Theory · Mathematics 2023-01-12 Emily Riehl

To a digraph with a choice of certain integral basis, we construct a CW complex, whose integral singular cohomology is canonically isomorphic to the path cohomology of the digraph as introduced in \cite{GLMY}. The homotopy type of the CW…

Combinatorics · Mathematics 2014-09-23 An Huang , Shing-Tung Yau

Immersions of graphs to the projective plane are studied. A classification of immersions up to regular homotopy is given. A complete invariant of immersions up to regular homotopy is constructed. Equivalence classes are described.

Geometric Topology · Mathematics 2017-03-21 Maxim A. Ivashkovskii

We begin the study the algebraic topology of semi-coarse spaces, which are generalizations of coarse spaces that enable one to endow non-trivial `coarse-like' structures to compact metric spaces, something which is impossible in coarse…

Algebraic Topology · Mathematics 2024-10-01 Antonio Rieser , Jonathan Treviño-Marroquín

Discrete homotopy theory or A-homotopy theory is a combinatorial homotopy theory defined on graphs, simplicial complexes, and metric spaces, reflecting information about their connectivity. The present paper aims to further understand the…

Combinatorics · Mathematics 2025-03-19 So Yamagata

Let $G$ be a group. The directed endomorphism graph, $\dend(G)$ of $G$ is a directed graph with vertex set $G$ and there is a directed edge from the vertex $a$ to the vertex $b$ if $a \neq b$ and there exists an endomorphism on $G$ mapping…

Group Theory · Mathematics 2025-11-20 Midhuna V Ajith , Peter J Cameron , Mainak Ghosh , Aparna Lakshmanan S

Persistent homology is a mathematical tool used for studying the shape of data by extracting its topological features. It has gained popularity in network science due to its applicability in various network mining problems, including…

Algebraic Topology · Mathematics 2023-06-21 Mehmet Emin Aktas , Thu Nguyen , Rakin Riza , Muhammad Ifte Islam , Esra Akbas

We propose to study homomorphisms of connectome graphs. Homomorphisms can be studied as sequences of elementary homomorphisms - folds, which identify pairs of vertices. Several fold types are defined. Initial computation results for some…

Neurons and Cognition · Quantitative Biology 2014-12-10 Peteris Daugulis

Like categories, small 2-categories have well-understood classifying spaces. In this paper, we deal with homotopy types represented by 2-diagrams of 2-categories. Our results extend to homotopy colimits of 2-functors lower categorical…

Category Theory · Mathematics 2015-04-24 A. M. Cegarra , B. A. Heredia

In a series of three papers we develop an end space theory for directed graphs. As for undirected graphs, the ends of a digraph are points at infinity to which its rays converge. Unlike for undirected graphs, some ends are joined by limit…

Combinatorics · Mathematics 2020-09-08 Carl Bürger , Ruben Melcher

D. K. Biss (Topology and its Applications 124 (2002) 355-371) introduced the topological fundamental group and presented some interesting basic properties of the notion. In this article we intend to extend the above notion to homotopy…

Algebraic Topology · Mathematics 2011-02-02 Helen Ghane , Zainab Hamed , Behrooz Mashayekhy , Hanieh Mirebrahimi

We prove that the category of directed graphs and graph maps carries a cofibration category structure in which the weak equivalences are the graph maps inducing isomorphisms on path homology.

Combinatorics · Mathematics 2025-12-23 Daniel Carranza , Brandon Doherty , Chris Kapulkin , Morgan Opie , Maru Sarazola , Liang Ze Wong

Two graphs are homomorphism indistinguishable over a graph class $\mathcal{F}$, denoted by $G \equiv_{\mathcal{F}} H$, if $\operatorname{hom}(F,G) = \operatorname{hom}(F,H)$ for all $F \in \mathcal{F}$ where $\operatorname{hom}(F,G)$…

Combinatorics · Mathematics 2023-07-11 Daniel Neuen

We introduce a persistent Hochschild homology framework for directed graphs. Hochschild homology groups of (path algebras of) directed graphs vanish in degree $i\geq 2$. To extend them to higher degrees, we introduce the notion of…

Algebraic Topology · Mathematics 2023-08-17 Luigi Caputi , Henri Riihimäki

In real-world systems, the relationships and connections between components are highly complex. Real systems are often described as networks, where nodes represent objects in the system and edges represent relationships or connections…

Algebraic Topology · Mathematics 2024-06-24 Shen Zhang