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Related papers: Planarity and dimension I

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Over the last 30 years, researchers have investigated connections between dimension for posets and planarity for graphs. Here we extend this line of research to the structural graph theory parameter tree-width by proving that the dimension…

Combinatorics · Mathematics 2016-12-14 Gwenaël Joret , Piotr Micek , Kevin G. Milans , William T. Trotter , Bartosz Walczak , Ruidong Wang

For P a poset or lattice, let Id(P) denote the poset, respectively, lattice, of upward directed downsets in P, including the empty set, and let id(P)=Id(P)-\{\emptyset\}. This note obtains various results to the effect that Id(P) is always,…

Rings and Algebras · Mathematics 2013-05-10 George M. Bergman

In 1977, Trotter and Moore proved that a poset has dimension at most $3$ whenever its cover graph is a forest, or equivalently, has treewidth at most $1$. On the other hand, a well-known construction of Kelly shows that there are posets of…

Combinatorics · Mathematics 2016-05-05 Gwenaël Joret , Piotr Micek , William T. Trotter , Ruidong Wang , Veit Wiechert

For a finite partially ordered set we calculate the dimension of the variety of its subspace representations having fixed dimension vector. The dimension is given in terms of the Euler quadratic form associated with a partially ordered set,…

Representation Theory · Mathematics 2019-02-27 Claudia Cavalcante Fonseca , Kostiantyn Iusenko

We study two new parameters for finite posets motivated by the problem of efficiently determining the set of successors of a given element. A plane map of a poset $P=(X,\leq)$ is an injective mapping of $X$ into the Cartesian plane…

Combinatorics · Mathematics 2026-05-21 Stefan Felsner , Jędrzej Hodor , Giacomo Ortali , Alexander Wolff

Let $G$ be a simple, undirected, finite graph with vertex set $V(G)$ and edge set $E(G)$. A $k$-dimensional box is a Cartesian product of closed intervals $[a_1,b_1]\times [a_2,b_2]\times...\times [a_k,b_k]$. The {\it boxicity} of $G$,…

Combinatorics · Mathematics 2010-03-12 Abhijin Adiga , Diptendu Bhowmick , L. Sunil Chandran

Let $f(n)$ be the largest integer such that every poset on $n$ elements has a $2$-dimensional subposet on $f(n)$ elements. What is the asymptotics of $f(n)$? It is easy to see that $f(n)\geqslant n^{1/2}$. We improve the best known upper…

Combinatorics · Mathematics 2017-11-28 Grzegorz Guśpiel , Piotr Micek , Adam Polak

In 2015, Felsner, Trotter, and Wiechert showed that posets with outerplanar cover graphs have bounded dimension. We generalise this result to posets with $k$-outerplanar cover graphs. Namely, we show that posets with $k$-outerplanar cover…

Combinatorics · Mathematics 2021-05-04 Maximilian Gorsky , Michał T. Seweryn

The metric dimension of a graph $G$ is the size of a smallest subset $L \subseteq V(G)$ such that for any $x,y \in V(G)$ with $x\not= y$ there is a $z \in L$ such that the graph distance between $x$ and $z$ differs from the graph distance…

Computational Complexity · Computer Science 2016-07-13 Josep Diaz , Olli Pottonen , Maria Serna , Erik Jan van Leeuwen

The "separation dimension" of a graph $G$ is the minimum positive integer $d$ for which there is an embedding of $G$ into $\mathbb{R}^d$, such that every pair of disjoint edges are separated by some axis-parallel hyperplane. We prove a…

Combinatorics · Mathematics 2021-07-01 Alex Scott , David R. Wood

The dimension of a partial order $P$ is the minimum number of linear orders whose intersection is $P$. There are efficient algorithms to test if a partial order has dimension at most $2$. In 1982 Yannakakis showed that for $k\geq 3$ to test…

Combinatorics · Mathematics 2016-04-26 Stefan Felsner , Irina Mustata , Martin Pergel

The original notion of dimension for posets is due to Dushnik and Miller and has been studied extensively in the literature. Quite recently, there has been considerable interest in two variations of dimension known as Boolean dimension and…

Combinatorics · Mathematics 2019-06-25 Fidel Barrera-Cruz , Thomas Prag , Heather Smith , Libby Taylor , William T. Trotter

One of possible cryptomorphic definitions of a partially ordered set (= a poset) $P$ on a non-empty finite basic set $N$ is in terms of the set ${\cal L}(P)$ of all its linear extensions, that is, in terms of the set of total orders of $N$…

Combinatorics · Mathematics 2025-11-25 Milan Studený , Václav Kratochvíl

The Dushnik--Miller dimension of a poset $P$ is the least $d$ for which $P$ can be embedded into a product of $d$ chains. Lewis and Souza showed that the dimension of the divisibility order on the interval of integers $[N/\kappa, N]$ is…

Combinatorics · Mathematics 2023-11-15 Milan Haiman

Nowhere dense graph classes provide one of the least restrictive notions of sparsity for graphs. Several equivalent characterizations of nowhere dense classes have been obtained over the years, using a wide range of combinatorial objects.…

Combinatorics · Mathematics 2019-02-04 Gwenaël Joret , Piotr Micek , Patrice Ossona de Mendez , Veit Wiechert

In 1981, Kelly showed that planar posets can have arbitrarily large dimension. However, the posets in Kelly's example have bounded Boolean dimension and bounded local dimension, leading naturally to the questions as to whether either…

Combinatorics · Mathematics 2020-10-28 Bartłomiej Bosek , Jarosław Grytczuk , William T. Trotter

In order theory, partially ordered sets are only equipped with one relation which decides the entire structure/Hasse diagram of the set. In this paper, we have presented how partially ordered sets can be studied under simultaneous partially…

General Mathematics · Mathematics 2023-07-03 Omprakash Atale

A quotient of a poset $P$ is a partial order obtained on the equivalence classes of an equivalence relation $\theta$ on $P$; $\theta$ is then called a congruence if it satisfies certain conditions, which vary according to different…

Combinatorics · Mathematics 2025-08-20 Nicholas J. Williams

In general, representations of interval orders may use an arbitrary set of interval lengths. We can define subclasses of interval orders by restricting the allowable lengths of intervals. Motivated by a recent paper of Keller, Trenk, and…

Combinatorics · Mathematics 2024-11-13 Csaba Biro , Sida Wan

Motivated by the study of the dimension of random posets, it was conjectured by Bollob\'as and Brightwell in 1997 that if $P$ is a finite poset whose cover graph contains at most one cycle then its order dimension is at most $3$. In this…

Combinatorics · Mathematics 2025-05-23 Antoine Abram , Adrien Segovia