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Related papers: Lower bound theorems for general polytopes

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We study the extension complexity of polytopes with few vertices or facets. On the one hand, we provide a complete classification of $d$-polytopes with at most $d+4$ vertices according to their extension complexity: Out of the…

Combinatorics · Mathematics 2016-09-14 Arnau Padrol

According to Euler's relation any polytope P has as many faces of even dimension as it has faces of odd dimension. As a generalization of this fact one can compare the number of faces whose dimension is congruent to i modulo m with the…

Combinatorics · Mathematics 2011-07-11 Laszlo Major

Let $d \geq 3$ be an integer. It is known that the number of edges of the edge polytope of the complete graph with $d$ vertices is $d(d-1)(d-2)/2$. In this paper, we study the maximum possible number $\mu_d$ of edges of the edge polytope…

Combinatorics · Mathematics 2018-08-22 Takayuki Hibi , Aki Mori , Hidefumi Ohsugi , Akihiro Shikama

Consider the question: Given integers $k<d<n$, does there exist a simple $d$-polytope with $n$ faces of dimension $k$? We show that there exist numbers $G(d,k)$ and $N(d,k)$ such that for $n> N(d,k)$ the answer is yes if and only if…

Combinatorics · Mathematics 2016-09-07 Anders Björner , Svante Linusson

We prove an upper bound of the form $2^{O(d^2 \mathrm{polylog}\,d)}$ on the number of affine (resp. linear) equivalence classes of, by increasing order of generality, 2-level d-polytopes, d-cones and d-configurations. This in particular…

Combinatorics · Mathematics 2018-06-18 Samuel Fiorini , Marco Macchia , Kanstantsin Pashkovich

Fine and Gill (1973) introduced the geometric representation for those comparative probability orders on n atoms that have an underlying probability measure. In this representation every such comparative probability order is represented by…

Combinatorics · Mathematics 2023-08-23 Ilya Chevyrev , Dominic Searles , Arkadii Slinko

Maxwell introduced a necessary minimum number of edges in terms of the number of vertices required for a graph to yield a Euclidean rigid generic framework in $\mathbb{R}^3$, this count was generalised to $\mathbb{R}^d$, for all $d\geq 1$.…

Combinatorics · Mathematics 2023-06-27 Jack Southgate

We study the problem of covering a given set of $n$ points in a high, $d$-dimensional space by the minimum enclosing polytope of a given arbitrary shape. We present algorithms that work for a large family of shapes, provided either only…

Computational Geometry · Computer Science 2007-05-23 Rina Panigrahy

We present explicit constructions of centrally symmetric polytopes with many faces: first, we construct a d-dimensional centrally symmetric polytope P with about (1.316)^d vertices such that every pair of non-antipodal vertices of P spans…

Metric Geometry · Mathematics 2011-11-21 Alexander Barvinok , Seung Jin Lee , Isabella Novik

We show that the graph of a simplicial polytope of dimension $d \ge 3$ has no nontrivial minimum edge cut with fewer than $d(d+1)/2$ edges, hence the graph is $\min\{\delta, d(d+1)/2\}$-edge-connected where $\delta$ denotes the minimum…

Combinatorics · Mathematics 2023-11-14 Vincent Pilaud , Guillermo Pineda-Villavicencio , Julien Ugon

We show that for fixed $d>3$ and $n$ growing to infinity there are at least $(n!)^{d-2 \pm o(1)}$ different labeled combinatorial types of $d$-polytopes with $n$ vertices. This is about the square of the previous best lower bounds. As an…

Combinatorics · Mathematics 2024-04-24 Arnau Padrol , Eva Philippe , Francisco Santos

A 1957 conjecture by Zdzislaw Melzak, that the unit volume polyhedron with least edge length was a triangular right prism, with edge length $2^{2/3}3^{11/6}$. We present a variety of necessary local criteria for any minimizer. In the case…

Metric Geometry · Mathematics 2023-04-21 Ásgeir Valfells

We show that the size of a minimal simplicial cover of a polytope $P$ is a lower bound for the size of a minimal triangulation of $P$, including ones with extra vertices. We then use this fact to study minimal triangulations of cubes, and…

Combinatorics · Mathematics 2007-05-23 Adam Bliss , Francis Edward Su

Although the Unimodality Conjecture holds for some certain classes of cubical polytopes (e.g. cubes, capped cubical polytopes, neighborly cubical polytopes), it fails for cubical polytopes in general. A 12-dimensional cubical polytope with…

Combinatorics · Mathematics 2015-01-07 László Major , Szabolcs Tóth

In this paper we present three different results dealing with the number of $(\leq k)$-facets of a set of points: 1. We give structural properties of sets in the plane that achieve the optimal lower bound $3\binom{k+2}{2}$ of $(\leq…

Combinatorics · Mathematics 2020-07-21 Oswin Aichholzer , Jesús García , David Orden , Pedro Ramos

Motivated by the search for reduced polytopes, we consider the following question: For which polytopes exists a vertex-facet assignment, that is, a matching between vertices and non-incident facets, so that the matching covers either all…

Combinatorics · Mathematics 2021-03-02 Thomas Jahn , Martin Winter

The Hirsch Conjecture (1957) stated that the graph of a $d$-dimensional polytope with $n$ facets cannot have (combinatorial) diameter greater than $n-d$. That is, that any two vertices of the polytope can be connected by a path of at most…

Combinatorics · Mathematics 2013-04-30 Francisco Santos

This paper considers the question of how to succinctly approximate a multidimensional convex body by a polytope. Given a convex body $K$ of unit diameter in Euclidean $d$-dimensional space (where $d$ is a constant) and an error parameter…

Computational Geometry · Computer Science 2022-12-09 Rahul Arya , Sunil Arya , Guilherme D. da Fonseca , David M. Mount

We investigate a novel setting for polytope rigidity, where a flex must preserve edge lengths and the planarity of faces, but is allowed to change the shapes of faces. For instance, the regular cube is flexible in this notion. We present…

Combinatorics · Mathematics 2026-03-11 Matthias Himmelmann , Bernd Schulze , Martin Winter

We introduce the property of convex normality of rational polytopes and give a dimensionally uniform lower bound for the edge lattice lengths, guaranteeing the property. As an application, we show that if every edge of a lattice d-polytope…

Combinatorics · Mathematics 2011-12-14 Joseph Gubeladze