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Related papers: Neighborly Cubical Polytopes and Spheres

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Neighborly cubical polytopes exist: for any $n\ge d\ge 2r+2$, there is a cubical convex d-polytope $C^n_d$ whose $r$-skeleton is combinatorially equivalent to that of the $n$-dimensional cube. This solves a problem of Babson, Billera &…

Combinatorics · Mathematics 2007-05-23 Michael Joswig , G"unter M. Ziegler

We construct a large family of neighborly polytopes that can be realized with all the vertices on the boundary of any smooth strictly convex body. In particular, we show that there are superexponentially many combinatorially distinct…

Metric Geometry · Mathematics 2015-06-25 Bernd Gonska , Arnau Padrol

Several recent papers have addressed the problem of characterizing the $f$-vectors of cubical polytopes. This is largely motivated by the complete characterization of the $f$-vectors of simplicial polytopes given by Stanley, Billera, and…

Combinatorics · Mathematics 2007-05-23 E. Babson , C. Chan

We construct examples of embedded flexible cross-polytopes in the spheres of all dimensions. These examples are interesting from two points of view. First, in dimensions 4 and higher, they are the first examples of embedded flexible…

Metric Geometry · Mathematics 2024-11-20 Alexander A. Gaifullin

For each $d\geq 3$ we construct cube complexes homeomorphic to the $d$-sphere with $n$ vertices in which the number of facets (assuming $d$ constant) is $\Omega(n^{5/4})$. This disproves a conjecture of Kalai's stating that the number of…

Combinatorics · Mathematics 2025-03-25 Sergey Avvakumov , Alfredo Hubard

Neighborly cubical polytopes are known as the cubical analogues of the cyclic polytopes. Using the short cubical $h$-vectors of cubical polytopes (introduced by Adin), we derive an explicit formula for the face numbers of the neighborly…

Combinatorics · Mathematics 2015-01-14 Laszlo Major

This article is covered by the article arxiv.1012.0925 We study intersection of two polyhedral spheres without self-intersections in 3-space. We find necessary and sufficient conditions on sequences x = x_1,x_2,...,x_n, y = y_1,y_2,...,y_n…

Metric Geometry · Mathematics 2011-12-13 Alexey Rukhovich

We construct the first examples of non-K\"ahler complex structures on $R^4$. These complex surfaces have some analogies with the complex structures constructed in early Fifties by Calabi and Eckmann on the products of two odd-dimensional…

Geometric Topology · Mathematics 2017-06-14 Antonio J. Di Scala , Naohiko Kasuya , Daniele Zuddas

Consider a polygon P and all neighboring circles (circles going through three consecutive vertices of P). We say that a neighboring circle is extremal if it is empty (no vertices of P inside) or full (no vertices of P outside). It is well…

Metric Geometry · Mathematics 2011-04-01 Arseniy Akopyan , Alexey Glazyrin , Oleg R. Musin , Alexey Tarasov

We show that every non-degenerate regular polytope can be used to construct a thin, residually-connected, chamber-transitive incidence geometry, i.e. a regular hypertope, with a tail-triangle Coxeter diagram. We discuss several interesting…

Combinatorics · Mathematics 2020-01-31 Antonio Montero , Asia Ivić Weiss

In this paper, we are concerned with $n$-dimensional spherical wavelets derived from the theory of approximate identities. For nonzonal bilinear wavelets introduced by Ebert \emph{et al.} in 2009 we prove isometry and Euclidean limit…

Functional Analysis · Mathematics 2018-03-07 Ilona Iglewska-Nowak

We show that nonlinear optimization techniques can successfully be applied to realize and to inscribe matroid polytopes and simplicial spheres. Thus we obtain a complete classification of neighborly polytopes of dimension $4$, $6$ and $7$…

Metric Geometry · Mathematics 2018-03-15 Moritz Firsching

We study intersection of two polyhedral spheres without self-intersections in 3-space. We find necessary and sufficient conditions on sequences x = x_1,x_2,...,x_n, y = y_1,y_2,...,y_n of positive integers, for existence of 2-dimensional…

Geometric Topology · Mathematics 2015-03-17 Alexey Rukhovich

In 1995, Jockusch constructed an infinite family of centrally symmetric $3$-dimensional simplicial spheres that are cs-$2$-neighborly. Here we generalize his construction and show that for all $d\geq 3$ and $n\geq d+1$, there exists a…

Combinatorics · Mathematics 2020-04-24 Isabella Novik , Hailun Zheng

The M-convexity of dual Schubert polynomials was first proven by Huh, Matherne, M\'esz\'aros, and St. Dizier in 2022. We give a full characterization of the supports of dual Schubert polynomials, which yields an elementary alternative proof…

Combinatorics · Mathematics 2024-11-26 Serena An , Katherine Tung , Yuchong Zhang

This paper is a survey of recent advances as well as open problems in the study of face numbers of centrally symmetric simplicial polytopes and spheres. The topics discussed range from neighborliness of centrally symmetric polytopes and the…

Combinatorics · Mathematics 2017-11-28 Isabella Novik

In this paper we show that graphs of "neighbourly" cubical complexes -- cubical complexes in which every pair of vertices spans a (unique) cube -- have good expansion properties, using a technique based on multicommodity flows. By showing…

Combinatorics · Mathematics 2007-05-23 Thomas Voigt

We provide a number of new construction techniques for cubical complexes and cubical polytopes, and thus for cubifications (hexahedral mesh generation). As an application we obtain an instance of a cubical 4-polytope that has a…

Combinatorics · Mathematics 2007-05-23 Alexander Schwartz , Guenter M. Ziegler

In this paper we study various scribability problems for polytopes. We begin with the classical $k$-scribability problem proposed by Steiner and generalized by Schulte, which asks about the existence of $d$-polytopes that cannot be realized…

Metric Geometry · Mathematics 2018-08-20 Hao Chen , Arnau Padrol

Inspired by the works of Adiprasito, Babson, Nevo, and Murai on the $g$-conjecture, we consider different classes of PL-spheres and the relations between them. We focus on a certain class of spheres that is in the intersection of…

Combinatorics · Mathematics 2019-06-20 Afshin Goodarzi
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