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Related papers: Sparsity and dimension

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We give new decomposition theorems for classes of graphs that can be transduced in first-order logic from classes of sparse graphs -- more precisely, from classes of bounded expansion and from nowhere dense classes. In both cases, the…

Logic in Computer Science · Computer Science 2022-01-27 Jan Dreier , Jakub Gajarský , Sandra Kiefer , Michał Pilipczuk , Szymon Toruńczyk

Let G be a subgraph-closed graph class with bounded maximum degree. We show that if G has balanced separators whose size is smaller than linear by a polynomial factor, then G has subexponential expansion. This gives a partial converse to a…

Combinatorics · Mathematics 2015-04-09 Zdenek Dvorak

We prove two theorems concerning incidence posets of graphs, cover graphs of posets and a related graph parameter. First, answering a question of Haxell, we show that the chromatic number of a graph is not bounded in terms of the dimension…

Combinatorics · Mathematics 2013-08-13 William T. Trotter , Ruidong Wang

The asymptotic dimension of metric spaces is an important notion in geometric group theory introduced by Gromov. The metric spaces considered in this paper are the ones whose underlying spaces are the vertex-sets of graphs and whose metrics…

Combinatorics · Mathematics 2021-09-08 Chun-Hung Liu

We prove that every poset with bounded cliquewidth and with sufficiently large dimension contains the standard example of dimension $k$ as a subposet. This applies in particular to posets whose cover graphs have bounded treewidth, as the…

Combinatorics · Mathematics 2025-10-21 Gwenaël Joret , Piotr Micek , Michał Pilipczuk , Bartosz Walczak

Over the past 10 years, there has been considerable interest in exploring questions connecting dimension for posets with graph theoretic properties of their cover graphs and order diagrams, especially with the concepts of planarity and…

Combinatorics · Mathematics 2023-04-18 Jędrzej Hodor , William T. Trotter

We present a linear-time algorithm for deciding first-order (FO) properties in classes of graphs with bounded expansion, a notion recently introduced by Nesetril and Ossona de Mendez. This generalizes several results from the literature,…

Discrete Mathematics · Computer Science 2015-03-19 Zdenek Dvorak , Daniel Kral , Robin Thomas

Nowhere dense graph classes, introduced by Nesetril and Ossona de Mendez, form a large variety of classes of "sparse graphs" including the class of planar graphs, actually all classes with excluded minors, and also bounded degree graphs and…

Logic in Computer Science · Computer Science 2014-01-28 Martin Grohe , Stephan Kreutzer , Sebastian Siebertz

Size-Ramsey numbers are a central notion in combinatorics and have been widely studied since their introduction by Erd\H{o}s, Faudree, Rousseau and Schelp in 1978. Research has mainly focused on the size-Ramsey numbers of $n$-vertex graphs…

Combinatorics · Mathematics 2023-09-06 Nemanja Draganić , Marc Kaufmann , David Munhá Correia , Kalina Petrova , Raphael Steiner

Inspired by a width invariant on permutations defined by Guillemot and Marx, Bonnet, Kim, Thomass\'e, and Watrigant introduced the twin-width of graphs, which is a parameter describing its structural complexity. This invariant has been…

Logic in Computer Science · Computer Science 2024-08-07 Édouard Bonnet , Jaroslav Nešetřil , Patrice Ossona de Mendez , Sebastian Siebertz , Stéphan Thomassé

In this short note, we relate the boxicity of graphs (and the dimension of posets) with their generalized coloring parameters. In particular, together with known estimates, our results imply that any graph with no $K_t$-minor can be…

Combinatorics · Mathematics 2019-01-21 Louis Esperet , Veit Wiechert

The dimension is a key measure of complexity of partially ordered sets. Small dimension allows succinct encoding. Indeed if $P$ has dimension $d$, then to know whether $x \leq y$ in $P$ it is enough to check whether $x\leq y$ in each of the…

Combinatorics · Mathematics 2019-12-12 Stefan Felsner , Tamás Mészáros , Piotr Micek

We introduce the Density Formula for (topological) drawings of graphs in the plane or on the sphere, which relates the number of edges, vertices, crossings, and sizes of cells in the drawing. We demonstrate its capability by providing…

Classes of graphs with bounded expansion are a generalization of both proper minor closed classes and degree bounded classes. Such classes are based on a new invariant, the greatest reduced average density (grad) of G with rank r,…

Combinatorics · Mathematics 2007-05-23 Jaroslav Nesetril , Patrice Ossona De Mendez

We introduce the concept of low rank-width colorings, generalising the notion of low tree-depth colorings introduced by Ne\v{s}et\v{r}il and Ossona de Mendez in [Grad and classes with bounded expansion I. Decompositions. EJC, 2008]. We say…

Data Structures and Algorithms · Computer Science 2019-07-29 O-joung Kwon , Michał Pilipczuk , Sebastian Siebertz

It has been known for more than 40 years that there are posets with planar cover graphs and arbitrarily large dimension. Recently, Streib and Trotter proved that such posets must have large height. In fact, all known constructions of such…

Combinatorics · Mathematics 2018-12-21 David M. Howard , Noah Streib , William T. Trotter , Bartosz Walczak , Ruidong Wang

The notions of bounded expansion and nowhere denseness not only offer robust and general definitions of uniform sparseness of graphs, they also describe the tractability boundary for several important algorithmic questions. In this paper we…

Discrete Mathematics · Computer Science 2019-09-25 Wojciech Nadara , Marcin Pilipczuk , Roman Rabinovich , Felix Reidl , Sebastian Siebertz

Asymptotic dimension and Assouad-Nagata dimension are measures of the large-scale shape of a class of graphs. Bonamy, Bousquet, Esperet, Groenland, Liu, Pirot, and Scott [J. Eur. Math. Society] showed that any proper minor-closed class has…

Combinatorics · Mathematics 2025-05-16 Marc Distel

Twin-width is a new parameter informally measuring how diverse are the neighbourhoods of the graph vertices, and it extends also to other binary relational structures, e.g. to digraphs and posets. It was introduced just very recently, in…

Discrete Mathematics · Computer Science 2021-07-09 Jakub Balabán , Petr Hliněný

We revisit the classical question of the relationship between the diameter of a graph and its expansion properties. One direction is well understood: expander graphs exhibit essentially the lowest possible diameter. We focus on the reverse…

Combinatorics · Mathematics 2017-11-23 Michael Dinitz , Michael Schapira , Gal Shahaf