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相关论文: On the diameter of lattice polytopes

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Geometrical objects with integral sides have attracted mathematicians for ages. For example, the problem to prove or to disprove the existence of a perfect box, that is, a rectangular parallelepiped with all edges, face diagonals and space…

组合数学 · 数学 2019-11-12 Sascha Kurz , Reinhard Laue

A lattice Delaunay polytope is known as perfect if the only ellipsoid, that can be circumscribed about it, is its Delaunay sphere. Perfect Delaunay polytopes are in one-to-one correspondence with arithmetic equivalence classes of positive…

度量几何 · 数学 2007-05-23 Mathieu Dutour , Robert Erdahl , Konstantin Rybnikov

The Ehrhart polynomial of an integral convex polytope counts the number of lattice points in dilates of the polytope. In math.CO/0402148, the authors conjectured that for any cyclic polytope with integral parameters, the Ehrhart polynomial…

组合数学 · 数学 2007-05-23 Fu Liu

We consider how flat a lattice simplex contained in the hypercube $[0,k]^d$ can be. This question is related to the notion of kissing polytopes: two lattice polytopes contained in the hypercube $[0,k]^d$ are kissing when they are disjoint…

度量几何 · 数学 2026-01-07 Antoine Deza , Lionel Pournin

We study the Minkowski length L(P) of a lattice polytope P, which is defined to be the largest number of non-trivial primitive segments whose Minkowski sum lies in P. The Minkowski length represents the largest possible number of factors in…

组合数学 · 数学 2012-07-31 Olivia Beckwith , Matthew Grimm , Jenya Soprunova , Bradley Weaver

It is proven here that the diameter of the d-dimensional associahedron is 2d-4 when d is greater than 9. Two maximally distant vertices of this polytope are explicitly described as triangulations of a convex polygon, and their distance is…

组合数学 · 数学 2014-03-31 Lionel Pournin

My main results are simple formulas for the surface area of d-dimensional lattice polytopes using Ehrhart theory.

组合数学 · 数学 2010-02-26 Gábor Hegedüs

It has been shown that the edge structure of the characteristic imset polytope is closely connected to the question of causal discovery. The diameter of a polytope is an indicator of how connected the polytope is and moreover gives us a…

组合数学 · 数学 2023-03-07 Petter Restadh

We explore upper bounds on the covering radius of non-hollow lattice polytopes. In particular, we conjecture a general upper bound of $d/2$ in dimension $d$, achieved by the "standard terminal simplices" and direct sums of them. We prove…

组合数学 · 数学 2022-09-07 Giulia Codenotti , Francisco Santos , Matthias Schymura

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…

组合数学 · 数学 2011-12-14 Joseph Gubeladze

The linear extension diameter of a finite poset P is the maximum distance between a pair of linear extensions of P, where the distance between two linear extensions is the number of pairs of elements of P appearing in different orders in…

组合数学 · 数学 2009-07-13 Stefan Felsner , Mareike Massow

We prove that any d-dimensional zonotope obtained from permutahedron by deleting zone vectors has belt diameter at most 3. Moreover if d is not greater than 6 then its belt diameter is bounded from above by 2. Also we show that these bounds…

组合数学 · 数学 2015-03-19 Alexey Garber

The diameter of a strongly connected $d$-dimensional simplicial complex is the diameter of its dual graph. We provide a probabilistic proof of the existence of $d$-dimensional simplicial complexes with diameter $ (\frac{1}{d \cdot d!} -…

组合数学 · 数学 2022-04-27 Tom Bohman , Andrew Newman

The extension complexity of a polytope measures its amenability to succinct representations via lifts. There are several versions of extension complexity, including linear, real semidefinite, and complex semidefinite. We focus on the last…

组合数学 · 数学 2021-10-18 Tristram Bogart , João Gouveia , Juan Camilo Torres

Brightwell, van den Heuvel and Stougie proved that the diameter of an $m \times n$ transportation polytope is at most $8(m+n-2)$, a factor of eight away from the Hirsch Conjecture. This bound was improved to $3(m+n-1)$ by Hurkens. We…

组合数学 · 数学 2012-05-15 Henning Bruhn-Fujimoto , Guillaume Chapuy , Edward D. Kim , Vincent Pilaud

We show that the number of lattice directions in which a d-dimensional convex body in R^d has minimum width is at most 3^d-1, with equality only for the regular cross-polytope. This is deduced from a sharpened version of the 3^d-theorem due…

组合数学 · 数学 2017-10-10 Jan Draisma , Tyrrell B. McAllister , Benjamin Nill

Denote by ${\mathcal K}^d$ the family of convex bodies in $E^d$ and by $w(C)$ the minimal width of $C \in {\mathcal K}^d$. We ask for the greatest number $\Lambda_n ({\mathcal K}^d)$ such that every $C \in {\mathcal K}^d$ contains a…

度量几何 · 数学 2017-03-30 Marek Lassak

We show that the volume of the inner $r$-neighborhood of a polytope in the $d$-dimensional Euclidean space is a pluri-phase Steiner-like function, i.e. a continuous piecewise polynomial function of degree $d$, proving thus a conjecture of…

度量几何 · 数学 2010-08-13 Sahin Kocak , Andrei V. Ratiu

For a given convex body K in $R^d$, a random polytope $K^{(n)}$ is defined (essentially) as the intersection of $n$ independent closed halfspaces containing $K$ and having an isotropic and (in a specified sense) uniform distribution. We…

度量几何 · 数学 2009-01-22 Károly J. Böröczky , Rolf Schneider

A theorem of Howe states that every 3-dimensional lattice polytope $P$ whose only lattice points are its vertices, is a Cayley polytope, i.e. $P$ is the convex hull of two lattice polygons with distance one. We want to generalize this…

组合数学 · 数学 2008-09-11 Jaron Treutlein