English
Related papers

Related papers: Flow polytopes for extensions of bipartite graphs

200 papers

We classify certain sofic shifts (the irreducible Point Extension Type, or PET, sofic shifts) up to flow equivalence, using invariants of the canonical Fischer cover. There are two main ingredients: (1) An extension theorem, for extending…

Dynamical Systems · Mathematics 2018-10-08 Mike Boyle , Toke Meier Carlsen , Søren Eilers

We prove an approximate max-multiflow min-multicut theorem for bounded treewidth graphs. In particular, we show the following: Given a treewidth-$r$ graph, there exists a (fractional) multicommodity flow of value $f$, and a multicut of…

Data Structures and Algorithms · Computer Science 2022-11-14 Tobias Friedrich , Davis Issac , Nikhil Kumar , Nadym Mallek , Ziena Zeif

A cubical polytope is a polytope with all its facets being combinatorially equivalent to cubes. The paper is concerned with the linkedness of the graphs of cubical polytopes. A graph with at least $2k$ vertices is \textit{$k$-linked} if,…

Combinatorics · Mathematics 2023-10-13 Hoa T. Bui , Guillermo Pineda-Villavicencio , Julien Ugon

We bound the volume of thick embeddings of finite graphs into the Heisenberg group, as well as the volume of coarse wirings of finite graphs into groups with polynomial growth. This work follows the work of Kolmogorov-Brazdin, Gromov-Guth…

Metric Geometry · Mathematics 2024-10-29 Or Kalifa

We identify a family of $O(|E(G)|^2)$ nontrivial facets of the connected matching polytope of a graph $G$, that is, the convex hull of incidence vectors of matchings in $G$ whose covered vertices induce a connected subgraph. Accompanying…

Combinatorics · Mathematics 2023-10-24 Phillippe Samer

We introduce one-way flows in near algebras and two-way flows in double near algebras with two interrelated multiplications. We establish parametric representations of the one-way and two-way flows in terms of a single element of the…

Rings and Algebras · Mathematics 2022-11-17 Włodzimierz Bryc , Jacek Wesołowski , Agnieszka Zięba

We call a bipartite graph {\it homogeneous} if every finite partial automorphism which respects left and right can be extended to a total automorphism. A $(\kappa,{\lambda} )$ bipartite graph is a bipartite graph with left side of size…

Logic · Mathematics 2009-09-25 Martin Goldstern , R. Grossberg , Menachem Kojman

Consider a graph $G$ with chromatic number $k$ and a collection of complete bipartite graphs, or bicliques, that cover the edges of $G$. We prove the following two results: \medskip \noindent $\bullet$ If the bicliques partition the edges…

Combinatorics · Mathematics 2009-03-19 Dhruv Mubayi , Sundar Vishwanathan

Symmetric edge polytopes of graphs are important object in Ehrhart theory,and have an application to Kuramoto models. In the present paper, we study the upper and lower bounds for the number of facets of symmetric edge polytopes of…

Combinatorics · Mathematics 2025-05-01 Aki Mori , Kenta Mori , Hidefumi Ohsugi

We prove that any globular subdivision of multipointed $d$-spaces gives rise to a dihomotopy equivalence between the associated flows. As a straightforward application, the flows associated to two multipointed $d$-spaces related by a finite…

Algebraic Topology · Mathematics 2026-01-30 Philippe Gaucher

Twin-width is a newly introduced graph width parameter that aims at generalizing a wide range of "nicely structured" graph classes. In this work, we focus on obtaining good bounds on twin-width $\text{tww}(G)$ for graphs $G$ from a number…

Discrete Mathematics · Computer Science 2022-01-25 Hugo Jacob , Marcin Pilipczuk

We prove that for every $n$-vertex graph $G$, the extension complexity of the correlation polytope of $G$ is $2^{O(\mathrm{tw}(G) + \log n)}$, where $\mathrm{tw}(G)$ is the treewidth of $G$. Our main result is that this bound is tight for…

Discrete Mathematics · Computer Science 2018-10-19 Pierre Aboulker , Samuel Fiorini , Tony Huynh , Marco Macchia , Johanna Seif

In some applications of matching, the structural or hierarchical properties of the two graphs being aligned must be maintained. The hierarchical properties are induced by the direction of the edges in the two directed graphs. These…

Data Structures and Algorithms · Computer Science 2009-09-29 Sean M. Falconer , Dmitri Maslov

In 2007, Chow and Glickenstein considered a linear semi-discrete analogue of the second-order curve shortening flow for smooth closed curves. In this article, we consider linear semi-discrete analogues of the polyharmonic curve diffusion…

Classical Analysis and ODEs · Mathematics 2025-02-11 James McCoy , Jahne Meyer

The dual of a planar graph $G$ is a planar graph $G^*$ that has a vertex for each face of $G$ and an edge for each pair of adjacent faces of $G$. The profound relationship between a planar graph and its dual has been the algorithmic basis…

Distributed, Parallel, and Cluster Computing · Computer Science 2025-10-23 Yaseen Abd-Elhaleem , Michal Dory , Merav Parter , Oren Weimann

The "edge polytope" of a finite graph G is the convex hull of the columns of its vertex-edge incidence matrix. We study extremal problems for this class of polytopes. For k =2, 3, 5 we determine the maximum number of vertices of…

Combinatorics · Mathematics 2014-06-30 Tuan Tran , Günter M. Ziegler

We present faster algorithms for approximate maximum flow in undirected graphs with good separator structures, such as bounded genus, minor free, and geometric graphs. Given such a graph with $n$ vertices, $m$ edges along with a recursive…

Data Structures and Algorithms · Computer Science 2012-10-19 Gary Miller , Richard Peng

We consider the multilinear polytope defined as the convex hull of the set of binary points satisfying a collection of multilinear equations. The complexity of the facial structure of the multilinear polytope is closely related to the…

Combinatorics · Mathematics 2023-08-30 Alberto Del Pia , Aida Khajavirad

In 2021, motivated by graph limit theory Lov\'asz extended most of the theory of flows to a measure theoretic setting. Using this framework, the first author constructed $d$-regular treeings that are measurably bipartite, and have no…

Combinatorics · Mathematics 2025-12-22 Gábor Kun , László Márton Tóth

We show that the left/right relation on the set of s-t-paths of a plane graph induces a so-called submodular lattice. If the embedding of the graph is s-t-planar, this lattice is even consecutive. This implies that Ford and Fulkerson's…

Discrete Mathematics · Computer Science 2012-11-12 Jannik Matuschke , Britta Peis
‹ Prev 1 8 9 10 Next ›