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Related papers: Maximum Betti numbers of \v{C}ech complexes

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In 2021, Ordentlich, Regev and Weiss made a breakthrough that the lattice covering density of any $n$-dimensional convex body is upper bounded by $cn^{2}$, improving on the best previous bound established by Rogers in 1959. However, for the…

Metric Geometry · Mathematics 2025-06-04 Matthias Schymura , Jun Wang , Fei Xue

We consider the problem of lower bounding a generalized Minkowski measure of subsets of a convex body with a log-concave probability measure, conditioned on the set size. A bound is given in terms of diameter and set size, which is sharp…

Functional Analysis · Mathematics 2007-05-23 Ravi Montenegro

Let $\mathrm{R}$ be a real closed field. The problem of obtaining tight bounds on the Betti numbers of semi-algebraic subsets of $\mathrm{R}^k$ in terms of the number and degrees of the defining polynomials has been an important problem in…

Algebraic Geometry · Mathematics 2016-10-06 Saugata Basu , Cordian Riener

We relate the maximum semidefinite and linear extension complexity of a family of polytopes to the cardinality of this family and the minimum pairwise Hausdorff distance of its members. This result directly implies a known lower bound on…

Optimization and Control · Mathematics 2016-05-30 Gennadiy Averkov , Volker Kaibel , Stefan Weltge

Given a set $\Sigma$ of spheres in $\mathbb{E}^d$, with $d\ge{}3$ and $d$ odd, having a fixed number of $m$ distinct radii $\rho_1,\rho_2,...,\rho_m$, we show that the worst-case combinatorial complexity of the convex hull $CH_d(\Sigma)$ of…

Computational Geometry · Computer Science 2011-06-14 Menelaos I. Karavelas , Eleni Tzanaki

We give an upper bound on the number of rational points of an arbitrary Zariski closed subset of a projective space over a finite field. This bound depends only on the dimensions and degrees of the irreducible components and holds for very…

Algebraic Geometry · Mathematics 2015-11-03 Alain Couvreur

We prove that the Random-Edge simplex algorithm requires an expected number of at most 13n/sqrt(d) pivot steps on any simple d-polytope with n vertices. This is the first nontrivial upper bound for general polytopes. We also describe a…

Combinatorics · Mathematics 2008-07-15 Bernd Gärtner , Volker Kaibel

A finite set of real numbers is called convex if the differences between consecutive elements form a strictly increasing sequence. We show that, for any pair of convex sets $A, B\subset\mathbb R$, each of size $n^{1/2}$, the convex grid…

Combinatorics · Mathematics 2015-04-28 Orit E. Raz , Micha Sharir , Ilya D. Shkredov

We prove that the height of any algebraic computation tree for deciding membership in a semialgebraic set is bounded from below (up to a multiplicative constant) by the logarithm of m-th Betti number (with respect to singular homology) of…

Computational Complexity · Computer Science 2015-08-18 Nicolai Vorobjov , Andrei Gabrielov

We prove upper bounds on the graph diameters of polytopes in two settings. The first is a worst-case bound for polytopes defined by integer constraints in terms of the height of the integers and certain subdeterminants of the constraint…

Combinatorics · Mathematics 2022-09-16 Hariharan Narayanan , Rikhav Shah , Nikhil Srivastava

We prove that the highest density of non-overlapping translates of a given centrally symmetric convex domain relative to its outer parallel domain of given outer radius is attained by a lattice packing in the Euclidean plane. This…

Metric Geometry · Mathematics 2025-12-30 Károly Bezdek , Zsolt Lángi

This paper is devoted to the study of lower and upper bounds for the number of vertices of the polytope of $n\times n\times n$ stochastic tensors (i.e., triply stochastic arrays of dimension $n$). By using known results on polytopes (i.e.,…

Combinatorics · Mathematics 2017-02-15 Zhongshan Li , Fuzhen Zhang , Xiao-Dong Zhang

We prove tight upper bounds for the number of vertices of a simple polygon that is the union or the intersection of two simple polygons with given numbers of convex and concave vertices. The similar question on graphs of the lower (or…

Combinatorics · Mathematics 2013-11-27 Pavel Kozhevnikov

In this paper, we compute the tightest possible bounds on the probability that the optimal value of a combinatorial optimization problem in maximization form with a random objective exceeds a given number, assuming only knowledge of the…

Optimization and Control · Mathematics 2022-11-24 Divya Padmanabhan , Selin Damla Ahipasaoglu , Arjun Ramachandra , Karthik Natarajan

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

Let V be a finite set of points in Euclidean d-space (d >= 2). The intersection of all unit balls B(v,1) centered at v, where v ranges over V, henceforth denoted by B(V) is the ball polytope associated with V. Note that B(V) is non-empty…

Metric Geometry · Mathematics 2009-05-12 Yaakov S. Kupitz , Horst Martini , Micha A. Perles

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

We investigate lower bounds for the number of ideal and finite vertices of right-angled hyperbolic polyhedra of finite volume. We use a geometric method of orthogonal gluings to establish new bounds in low dimensions, specifically…

Combinatorics · Mathematics 2026-04-01 Andrey Egorov

A bound for Betti numbers of sets definable in o-minimal structures is presented. An axiomatic complexity measure is defined, allowing various concrete complexity measures for definable functions to be covered. This includes common concrete…

Logic · Mathematics 2012-05-22 Mahana Clutha

We prove graded bounds on the individual Betti numbers of affine and projective complex varieties. In particular, we give for each $p,d,r$, explicit bounds on the $p$-th Betti numbers of affine and projective subvarieties of $\mathrm{C}^k$,…

Algebraic Geometry · Mathematics 2016-07-20 Saugata Basu , Cordian Riener