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Related papers: Whitney's 2-isomorphism theorem for graphings

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In \cite{Elek} we proved that the limit of a weakly convergent sequence of finite graphs can be viewed as a graphing or a continuous field of infinite graphs. Thus one can associate a type $II_1$-von Neumann algebra to such graph sequences.…

Combinatorics · Mathematics 2007-05-23 Gábor Elek

Let $\beta>0$. Motivated by jumbled graphs defined by Thomason, the celebrated expander mixing lemma and Haemers's vertex separation inequality, we define that a graph $G$ with $n$ vertices is a weakly $(n,\beta)$-graph if $\frac{|X|…

Combinatorics · Mathematics 2022-05-31 Xiaofeng Gu , Muhuo Liu

We construct a sequence of finite graphs that weakly converge to a Cayley graph, but there is no labelling of the edges that would converge to the corresponding Cayley diagram. A similar construction is used to give graph sequences that…

Combinatorics · Mathematics 2020-05-11 Adam Timar

One can describe isomorphism of two compact hyperbolic Riemann surfaces of the same genus by a measure-theoretic property: a chosen isomorphism of their fundamental groups corresponds to a homeomorphism on the boundary of the Poincar\'e…

Algebraic Geometry · Mathematics 2011-12-22 Gunther Cornelissen , Janne Kool

In recent work, Stokes and Vermant considered graph-of-groups realisations of hypergraphs as a new description of rigidity-theoretic problems. In this paper, we show that the infinitesimal aspects of graph-of-groups realisations can be…

Combinatorics · Mathematics 2026-04-03 Joannes Vermant

We study the properties of finite graphs in which the ball of radius $r$ around each vertex induces a graph isomorphic to some fixed graph $F$. This is a natural extension of the study of regular graphs, and of the study of graphs of…

Combinatorics · Mathematics 2016-12-21 Itai Benjamini , David Ellis

The concept of graph flattenability, initially formalized by Belk and Connelly and later expanded by Sitharam and Willoughby, extends the question of embedding finite metric spaces into a given normed space. A finite simple graph $G=(V,E)$…

Metric Geometry · Mathematics 2024-05-06 Sean Dewar , Eleftherios Kastis , Derek Kitson , William Sims

In their seminal paper from 2004, Kuhn, Moscibroda, and Wattenhofer (KMW) proved a hardness result for several fundamental graph problems in the LOCAL model: For any (randomized) algorithm, there are input graphs with $n$ nodes and maximum…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-05-10 Corinna Coupette , Christoph Lenzen

We prove a new generalisation of Ramsey's theorem by showing that every $2$-edge-coloured graph with sufficiently large minimum degree contains a monochromatic induced subgraph whose minimum degree remains large. From this, we also derive…

Combinatorics · Mathematics 2026-04-17 Arnab Char , Ken-ichi Kawarabayashi , Lucas Picasarri-Arrieta

For all Artin groups, we characterise the girth (i.e. the length of a shortest cycle) of the defining graph algebraically, showing that it is an isomorphism invariant. Using this result, we prove that the Artin groups based on a cycle graph…

Group Theory · Mathematics 2026-01-09 Giovanni Sartori

We establish spherical variants of the Gleason-Kahane-Zelazko and Kowalski-S{\l}odkowski theorems, and we apply them to prove that every weak-2-local isometry between two uniform algebras is a linear map. Among the consequences, we solve a…

Functional Analysis · Mathematics 2017-05-11 Lei Li , Antonio M. Peralta , Liguang Wang , Ya-Shu Wang

In this article we introduce the notion of weak harmonic labeling of a graph, a generalization of the concept of harmonic labeling defined recently by Benjamini et al. that allows extension to finite graphs and graphs with leaves. We…

Combinatorics · Mathematics 2020-12-01 Pablo Leandro Bonucci , Nicolás Ariel Capitelli

We prove several results showing that every locally finite Borel graph whose large-scale geometry is "tree-like" induces a treeable equivalence relation. In particular, our hypotheses hold if each component of the original graph either has…

Logic · Mathematics 2025-04-02 Ruiyuan Chen , Antoine Poulin , Ran Tao , Anush Tserunyan

It is confirmed in this work that the graph isomorphism can be tested in polynomial time, which resolves a longstanding problem in the theory of computation. The contributions are in three phases as follows. 1. A description graph…

Computational Complexity · Computer Science 2023-01-25 Rui Xue

A graph G is weakly 4-connected if it is 3-connected, has at least five vertices, and for every pair of sets (A,B) with union V(G) and intersection of size three such that no edge has one end in A-B and the other in B-A, one of the induced…

Combinatorics · Mathematics 2014-01-14 Rajneesh Hegde , Robin Thomas

We show that if a sequence of dense graphs has the property that for every fixed graph F, the density of copies of F in these graphs tends to a limit, then there is a natural ``limit object'', namely a symmetric measurable 2-variable…

Combinatorics · Mathematics 2007-05-23 Laszlo Lovasz , Balazs Szegedy

A graph matroid family $\mathcal{M}$ is a family of matroids $\mathcal{M}(G)$ defined on the edge set of each finite graph $G$ in a compatible and isomorphism-invariant way. We say that $\mathcal{M}$ has the Whitney property if there is a…

Combinatorics · Mathematics 2026-03-04 Dániel Garamvölgyi

A digraph is 2-regular if every vertex has both indegree and outdegree two. We define an embedding of a 2-regular digraph to be a 2-cell embedding of the underlying graph in a closed surface with the added property that for every…

Combinatorics · Mathematics 2017-06-12 Dan Archdeacon , Matt DeVos , Stefan Hannie , Bojan Mohar

The criteria for determining graph isomorphism are crucial for solving graph isomorphism problems. The necessary condition is that two isomorphic graphs possess invariants, but their function can only be used to filtrate and subdivide…

Graphics · Computer Science 2025-08-19 Chuanfu Hu , Aimin Hou

A Riemann-Roch theorem on graph was initiated by M. Baker and S. Norine. In their article [2], a Riemann-Roch theorem on a finite graph with uniform vertex-weight and uniform edge-weight was established and it was suggested a Riemann-Roch…

Combinatorics · Mathematics 2022-01-20 Atsushi Atsuji , Hiroshi Kaneko
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