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Related papers: Partial duality and closed 2-cell embeddings

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Partial duality generalizes the fundamental concept of the geometric dual of an embedded graph. A partial dual is obtained by forming the geometric dual with respect to only a subset of edges. While geometric duality preserves the genus of…

Combinatorics · Mathematics 2013-11-18 Iain Moffatt

In this paper, we extend the recently introduced concept of partially dual ribbon graphs to graphs. We then go on to characterize partial duality of graphs in terms of bijections between edge sets of corresponding graphs. This result…

Combinatorics · Mathematics 2012-03-01 Iain Moffatt

A "folklore conjecture, probably due to Tutte" (as described in [P.D. Seymour, Sums of circuits, Graph theory and related topics (Proc. Conf., Univ. Waterloo, 1977), pp. 341-355, Academic Press, 1979]) asserts that every bridgeless cubic…

Combinatorics · Mathematics 2011-01-14 Bojan Mohar

We approach the cycle double cover conjecture by looking for a circular 2-cell embedding of cubic graphs on an arbitrary surface. It is easy to see that if such an embedding exists, we can get to it from an arbitrary starting 2-cell…

Combinatorics · Mathematics 2026-05-05 Babak Ghanbari , Robert Šámal

We investigate the structure of two-dimensional partial cubes, i.e., of isometric subgraphs of hypercubes whose vertex set defines a set family of VC-dimension at most 2. Equivalently, those are the partial cubes which are not contractible…

Combinatorics · Mathematics 2021-05-20 Victor Chepoi , Kolja Knauer , Manon Philibert

It is known that graphs cellularly embedded into surfaces are equivalent to ribbon graphs. In this work, we generalize this statement to broader classes of graphs and surfaces. Half-edge graphs extend abstract graphs and are useful in…

Combinatorics · Mathematics 2017-09-06 Remi C. Avohou , Joseph Ben Geloun , Mahouton N. Hounkonnou

We consider two operations on an edge of an embedded graph (or equivalently a ribbon graph): giving a half-twist to the edge and taking the partial dual with respect to the edge. These two operations give rise to an action of S_3^{|E(G)|},…

Combinatorics · Mathematics 2012-02-28 Joanna A. Ellis-Monaghan , Iain Moffatt

Recently, Chmutov introduced the partial duality of ribbon graphs, which can be regarded as a generalization of the classical Euler-Poincar\'e duality. The partial-dual genus polynomial $^\partial\varepsilon_G(z)$ is an enumeration of the…

Combinatorics · Mathematics 2025-09-03 Zhiyun Cheng

In a closed 2-cell embedding of a graph each face is homeomorphic to an open disk and is bounded by a cycle in the graph. The Orientable Strong Embedding Conjecture says that every 2-connected graph has a closed 2-cell embedding in some…

Combinatorics · Mathematics 2009-11-17 M. N. Ellingham , Xiaoya Zha

The first part of the paper centers in the study of embeddability between partially commutative groups. In [KK], for a finite simplicial graph $\Gamma$, the authors introduce an infinite, locally infinite graph $\Gamma^e$, called the…

Group Theory · Mathematics 2015-06-11 Montserrat Casals-Ruiz

The set of factorizations of permutations in to $m$ transpositions of some symmetric group $\mathcal{S}_n$ is naturally in bijection with the set of graphs of order $n$ and size $m$ with both edges and vertices labeled. We define a notion…

Combinatorics · Mathematics 2024-08-01 Nikos Apostolakis

Traditional representations of graphs and their duals suggest the requirement that the dual vertices be placed inside their corresponding primal faces, and the edges of the dual graph cross only their corresponding primal edges. We consider…

Computational Geometry · Computer Science 2007-05-23 C. Erten , S. G. Kobourov

We generalize the natural duality of graphs embedded into a surface to a duality with respect to a subset of edges. The dual graph might be embedded into a different surface. We prove a relation between the signed Bollobas-Riordan…

Combinatorics · Mathematics 2008-12-16 Sergei Chmutov

The $2$-cell embeddings of graphs on closed surfaces have been widely studied. It is well known that ($2$-cell) embedding a given graph $G$ on a closed orientable surface is equivalent to cyclically ordering the edges incident to each…

Combinatorics · Mathematics 2017-03-16 Ricky X. F. Chen , Christian M. Reidys

The $2$-cell embeddings of graphs on closed surfaces have been widely studied. It is well known that ($2$-cell) embedding a given graph $G$ on a closed orientable surface is equivalent to cyclically ordering the edges incident to each…

Combinatorics · Mathematics 2015-03-06 Ricky X. F. Chen , Christian M. Reidys

We initiate the study of computational complexity of graph coverings, aka locally bijective graph homomorphisms, for {\em graphs with semi-edges}. The notion of graph covering is a discretization of coverings between surfaces or topological…

Discrete Mathematics · Computer Science 2025-10-09 Jan Bok , Jiří Fiala , Petr Hliněný , Nikola Jedličková , Jan Kratochvíl

We study the problem of finding the minimal (maximal) genus for a surface where a given four-valent graph with fixed opposite edge structure can be embedded into. We find several partial relations and give new reformulations in…

Combinatorics · Mathematics 2008-04-29 Vassily Olegovich Manturov

This is an expository paper extending the tutorial talk at the MATRIX Workshop on Uniqueness and Discernment in Graph Polynomials in October 2023. The explanation is mainly based on the paper "Partial Duality of Hypermaps" by S.Chmutov and…

Geometric Topology · Mathematics 2024-04-09 Sergei Chmutov

The geometric dual of a cellularly embedded graph is a fundamental concept in graph theory and also appears in many other branches of mathematics. The partial dual is an essential generalization which can be obtained by forming the…

Combinatorics · Mathematics 2020-02-25 Xia Guo , Xian'an Jin , Qi Yan

An alternative foundation for 2-categories is explored by studying graph-theoretically a partial operation on 2-cells named juncture, which can replace vertical and horizontal composition. Juncture is a generalized vertical composition of…

Combinatorics · Mathematics 2015-05-07 Kosta Dosen , Zoran Petric
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