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Related papers: Perfect matchings in hyperfinite graphings

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We consider random perfect matchings on a general class of contracting bipartite graphs by letting certain edge weights be 0 on the contracting square-hexagon lattice in a periodic way. We obtain a deterministic limit shape in the scaling…

Probability · Mathematics 2021-01-07 Zhongyang Li

Consider the random process in which the edges of a graph $G$ are added one by one in a random order. A classical result states that if $G$ is the complete graph $K_{2n}$ or the complete bipartite graph $K_{n,n}$, then typically a perfect…

Combinatorics · Mathematics 2020-11-03 Roman Glebov , Zur Luria , Michael Simkin

Hyperfiniteness or amenability of measurable equivalence relations and group actions has been studied for almost fifty years. Recently, unexpected applications of hyperfiniteness were found in computer science in the context of testability…

Functional Analysis · Mathematics 2012-05-31 Gabor Elek

We show that the ratio of the number of near perfect matchings to the number of perfect matchings in $d$-regular strong expander (non-bipartite) graphs, with $2n$ vertices, is a polynomial in $n$, thus the Jerrum and Sinclair Markov chain…

Data Structures and Algorithms · Computer Science 2021-03-17 Farzam Ebrahimnejad , Ansh Nagda , Shayan Oveis Gharan

Let $G$ be a matching-covered graph, i.e., every edge is contained in a perfect matching. An edge subset $X$ of $G$ is feasible if there exists two perfect matchings $M_1$ and $M_2$ such that $|M_1\cap X|\not\equiv |M_2\cap X| \pmod 2$.…

Combinatorics · Mathematics 2017-03-20 Jinghua He , Erling Wei , Dong Ye , Shaohui Zhai

In this paper we study the main characteristics of some evaluation codes parameterized by the edges of a bipartite graph with a perfect matching.

Combinatorics · Mathematics 2022-10-04 Manuel Gonzalez Sarabia , Rafael H. Villarreal

We consider bipartite graphs definable in o-minimal structures, in which the edge relation $G$ is a finite union of graphs of certain measure-preserving maps. We establish a fact on the existence of definable matchings with few short…

Logic · Mathematics 2023-05-10 Jana Maříková

A connected graph, on four or more vertices, is matching covered (aka 1-extendable) if every edge is present in some perfect matching. An ear decomposition theorem exists for bipartite matching covered graphs due to Hetyei. From the results…

Combinatorics · Mathematics 2026-05-21 Amit Kumar Mallik , Ajit A. Diwan , Nishad Kothari

We investigate the space complexity of certain perfect matching problems over bipartite graphs embedded on surfaces of constant genus (orientable or non-orientable). We show that the problems of deciding whether such graphs have (1) a…

Computational Complexity · Computer Science 2010-04-29 Samir Datta , Raghav Kulkarni , Raghunath Tewari , N. V. Vinodchandran

A connected graph G is called matching covered if every edge of G is contained in a perfect matching. Perfect matching width is a width parameter for matching covered graphs based on a branch decomposition. It was introduced by Norine and…

Combinatorics · Mathematics 2019-02-15 Meike Hatzel , Roman Rabinovich , Sebastian Wiederrecht

The classical theorem of Vizing states that every graph of maximum degree $d$ admits an edge-coloring with at most $d+1$ colors. Furthermore, as it was earlier shown by K\H{o}nig, $d$ colors suffice if the graph is bipartite. We investigate…

Combinatorics · Mathematics 2016-08-23 Endre Csóka , Gabor Lippner , Oleg Pikhurko

We exhibit an analogy between the problem of pushing forward measurable sets under measure preserving maps and linear relaxations in combinatorialoptimization. We show how invariance of hyperfiniteness of graphings under local isomorphism…

Combinatorics · Mathematics 2021-02-17 László Lovász

We consider, for complete bipartite graphs, the convex hulls of characteristic vectors of all matchings, extended by a binary entry indicating whether the matching contains two specific edges. These polytopes are associated to the quadratic…

Discrete Mathematics · Computer Science 2019-04-09 Matthias Walter

Extending the work of Godsil and others, we investigate the notion of the inverse of a graph (specifically, of bipartite graphs with a unique perfect matching). We provide a concise necessary and sufficient condition for the invertibility…

Combinatorics · Mathematics 2011-08-19 Cam McLeman , Erin McNicholas

In this note, we prove an interesting result about perfect matchings in a complete bipartite graph with 2n vertices on each side, whose edges are colored in red and blue such that each vertex is part of n red edges and n blue edges.

Combinatorics · Mathematics 2025-08-11 Tudor Popescu

Nash-Williams proved that every graph has a well-balanced orientation. A key ingredient in his proof is admissible odd-vertex pairings. We show that for two slightly different definitions of admissible odd-vertex pairings, deciding whether…

Combinatorics · Mathematics 2022-06-15 Florian Hörsch

We prove that a fractional perfect matching in a non-bipartite graph can be written, in polynomial time, as a convex combination of perfect matchings. This extends the Birkhoff-von Neumann Theorem from bipartite to non-bipartite graphs. The…

Data Structures and Algorithms · Computer Science 2020-10-16 Vijay V. Vazirani

One of possible interpretations of the well-known K\"onig--Hall--Egerv\'ary theorem is a full characterization of all bipartite graphs extremal for fractional matchings of a given weight (or, equivalently, a characterization of…

Combinatorics · Mathematics 2020-12-16 Anna A. Taranenko

Let $G$ be a bipartite graph and its adjacency matrix $\mathbb A$. If $G$ has a unique perfect matching, then $\mathbb A$ has an inverse $\mathbb A^{-1}$ which is a symmetric integral matrix, and hence the adjacency matrix of a multigraph.…

Combinatorics · Mathematics 2018-03-09 Yujun Yang , Dong Ye

We study the relationship between hyperfiniteness and problems in Borel graph combinatorics by adapting game-theoretic techniques introduced by Marks to the hyperfinite setting. We compute the possible Borel chromatic numbers and edge…