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A biconvex polytope is a classical and tropical convex hull of finitely many points. Given a biconvex polytope, for each vertex of it we construct a directed bigraph and a gammoid so that the collection of base polytopes of those gammoids…

Algebraic Geometry · Mathematics 2022-12-21 Jaeho Shin

The aim of this article is to show the existence, and also give an explicit construction, of infinite sets of orthogonal exponentials for certain families of convex polytopes which include simple-rational polytopes and also non simple…

Combinatorics · Mathematics 2019-09-19 Yehonatan Salman

The main motivation here is a question: whether any polyhedron which can be subdivided into convex pieces without adding a vertex, and which has the same vertices as a convex polyhedron, is infinitesimally rigid. We prove that it is indeed…

Differential Geometry · Mathematics 2007-05-23 Robert Connelly , Jean-Marc Schlenker

Let $2\le k\le d-1$ and let $P$ and $Q$ be two convex polytopes in ${\mathbb E^d}$. Assume that their projections, $P|H$, $Q|H$, onto every $k$-dimensional subspace $H$, are congruent. In this paper we show that $P$ and $Q$ or $P$ and $-Q$…

Metric Geometry · Mathematics 2017-09-22 Sergii Myroshnychenko , Dmitry Ryabogin

It is proved that if $C$ is a convex body in ${\Bbb R}^n$ then $C$ has an affine image $\widetilde C$ (of non-zero volume) so that if $P$ is any 1-codimensional orthogonal projection, $$|P\widetilde C| \ge |\widetilde C|^{n-1\over n}.$$ It…

Metric Geometry · Mathematics 2016-09-06 Keith Ball

An equidistant polytope is a special equidistant set in the space $\mathbb{R}^n$ all of whose boundary points have equal distances from two finite systems of points. Since one of the finite systems of the given points is required to be in…

Metric Geometry · Mathematics 2021-12-16 Csaba Vincze , Márk Oláh , Letícia Lengyel

We present structures comprised of identical convex polyhedra which are interlocked geometrically. These sets cannot be disassembled by removing individual polyhedra by translations and/or rotations. The shapes that permit interlocking…

Metric Geometry · Mathematics 2017-12-05 A. J. Kanel-Belov , A. V. Dyskin , Y. Estrin , E. Pasternak , I. A. Ivanov-Pogodaev

This is a survey on algorithmic questions about combinatorial and geometric properties of convex polytopes. We give a list of 35 problems; for each the current state of knowledege on its theoretical complexity status is reported. The…

Combinatorics · Mathematics 2007-05-23 Volker Kaibel , Marc E. Pfetsch

We characterize the polytopes in $\mathbb{R}^d$ (not necessarily convex or connected ones) which multi-tile the space by translations along a given lattice. We also give a necessary and sufficient condition for two polytopes in…

Combinatorics · Mathematics 2019-10-30 Nir Lev , Bochen Liu

In convex geometry, the constructions that assign to a convex body its difference body, projection body, or volume have the following properties: They are (1) invariant under volume-preserving linear changes of coordinates; (2) continuous;…

Metric Geometry · Mathematics 2024-02-12 Jakob Henkel , Thomas Wannerer

We study the expected volume of random polytopes generated by taking the convex hull of independent identically distributed points from a given distribution. We show that for log-concave distributions supported on convex bodies, we need at…

Metric Geometry · Mathematics 2021-11-16 Debsoumya Chakraborti , Tomasz Tkocz , Beatrice-Helen Vritsiou

This paper proves the following statement: If a convex body can form a three or fourfold translative tiling in the three-dimensional space, it must be a parallelohedron. In other words, it must be a parallelotope, a hexagonal prism, a…

Metric Geometry · Mathematics 2021-10-01 Mei Han , Kirati Sriamorn , Qi Yang , Chuanming Zong

We prove the theorem mentioned in the title, for ${\mathbb{R}}^n$, where $n \ge 3$. The case of the simplex was known previously. Also, the case $n=2$ was settled, but there the infimum was some well-defined function of the side lengths. We…

Differential Geometry · Mathematics 2017-07-28 N. V. Abrosimov , E. Makai, , A. D. Mednykh , Yu. G. Nikonorov , G. Rote

Polytopes are the basic finite data structures for convex sets: they appear as feasible regions in linear optimization, as geometric summaries in algorithms, and as random objects in stochastic geometry. A natural geometric question is…

Metric Geometry · Mathematics 2026-03-10 Steven Hoehner

For convex partitions of a convex body $B$ we prove that we can put a homothetic copy of $B$ into each set of the partition so that the sum of homothety coefficients is $\ge 1$. In the plane the partition may be arbitrary, while in higher…

Combinatorics · Mathematics 2012-12-27 Arseniy Akopyan , Roman Karasev

This short note extends a recent result (Bonifas et al, On sub-determinants and the diameter of polyhedra, Discrete Computational Geometry, 52, 2014) of an upper bound of the diameter of a convex polytope defined by an integer matrix to a…

Metric Geometry · Mathematics 2020-12-09 Yaguang Yang

A shape of a combinatorial polytope is a convex embedding into Euclidean space. We provide necessary and sufficient conditions for a piecewise linear map between two shapes of the same polytope to be a compression (respectively a weak…

Metric Geometry · Mathematics 2025-06-24 José Ayala , David Kirszenblat , J. Hyam Rubinstein

We prove that the Hilbert Geometry of a convex set is bi-lipschitz equivalent to a normed vector space if and only if the convex is a polytope.

Differential Geometry · Mathematics 2014-12-10 Constantin Vernicos

A convex polygon is defined as a sequence (V_0,...,V_{n-1}) of points on a plane such that the union of the edges [V_0,V_1],..., [V_{n-2},V_{n-1}], [V_{n-1},V_0] coincides with the boundary of the convex hull of the set of vertices…

General Mathematics · Mathematics 2007-05-23 Iosif Pinelis

While there is extensive literature on approximation of convex bodies by inscribed or circumscribed polytopes, much less is known in the case of generally positioned polytopes. Here we give upper and lower bounds for approximation of convex…

Probability · Mathematics 2021-03-03 Steven D. Hoehner , Carsten Schuett , Elisabeth M. Werner