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Related papers: The computational complexity of convex bodies

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We survey results concerning sharp estimates on volumes of sections and projections of certain convex bodies, mainly $\ell_p$ balls, by and onto lower dimensional subspaces. This subject emerged from geometry of numbers several decades ago…

Functional Analysis · Mathematics 2025-01-28 Piotr Nayar , Tomasz Tkocz

In this article we pose the problem of existence and uniqueness of convex body for which the projection curvature radius function coincides with given function. We find a necessary and sufficient condition that ensures a positive answer to…

Differential Geometry · Mathematics 2016-09-07 Aramyan Rafik

Let $K$ be a convex body in $\mathbb R^n$. We prove that in small codimensions, the sections of a convex body through the centroid are quite symmetric with respect to volume. As a consequence of our estimates we give a positive answer to a…

Metric Geometry · Mathematics 2016-04-20 Matthieu Fradelizi , Mathieu Meyer , Vlad Yaskin

We provide convex body domination results for the generalized vector-valued commutator of those operators that admit specific forms of convex body domination themselves. We also prove some strong type estimates and other consequences of…

Functional Analysis · Mathematics 2026-04-14 Joshua Isralowitz , Israel P. Rivera-Ríos , Francisco Sáez-Rivas

This paper proposes a novel and simple algorithm of facet enumeration for convex polytopes. The complexity of the algorithm is discussed. The algorithm is implemented in Matlab. Some simple polytopes with known H-representations and…

Optimization and Control · Mathematics 2025-01-23 Yaguang Yang

Motivated by a problem on the 67th William Lowell Putnam Mathematical Competition, we will summarize three different solutions found on a website. This Putman problem is a special case of Sylvester's four point problem! Suppose four points…

Metric Geometry · Mathematics 2021-09-14 Sheree Sharpe

We consider moments of the normalized volume of a symmetric or nonsymmetric random polytope in a fixed symmetric convex body. We investigate for which bodies these moments are extremized, and calculate exact values in some of the extreme…

Metric Geometry · Mathematics 2007-05-23 Mark W. Meckes

The concept of a visible point of a convex set relative to a given point is introduced. A number of basic properties of such visible point sets is developed. In particular, it is shown that this concept is useful in the study of best…

Functional Analysis · Mathematics 2012-11-07 Frank Deutsch , Hein Hundal , Ludmil Zikatanov

We introduce polystar bodies: compact starshaped sets whose gauge or radial functions are expressible by polynomials, enabling tractable computations, such as that of intersection bodies. We prove that polystar bodies are uniformly dense in…

Optimization and Control · Mathematics 2025-06-02 Chiara Meroni , Jared Miller , Mauricio Velasco

In this work, we present a new efficient method for convex shape representation, which is regardless of the dimension of the concerned objects, using level-set approaches. Convexity prior is very useful for object completion in computer…

Computer Vision and Pattern Recognition · Computer Science 2020-03-24 Lingfeng li , Shousheng Luo , Xue-Cheng Tai , Jiang Yang

Approximating convex bodies is a fundamental problem in geometry. Given a convex body $K$ in $\mathbb{R}^d$ for a fixed dimension $d$, the objective is to minimize the number of facets of an approximating polytope for a given Hausdorff…

Computational Geometry · Computer Science 2026-01-26 Sunil Arya , Guilherme D. da Fonseca , David M. Mount

A subset of a convex body $B$ containing the origin in a Euclidean space is {\it parkable in $B$} if it can be translated inside $B$ in such a manner that the translate the origin. We provide characterizations of ellipsoids and of centrally…

Metric Geometry · Mathematics 2016-03-30 Alexandru Chirvasitu

The X-ray numbers of some classes of convex bodies are investigated. In particular, we give a proof of the X-ray Conjecture as well as of the Illumination Conjecture for almost smooth convex bodies of any dimension and for convex bodies of…

Metric Geometry · Mathematics 2011-09-29 Karoly Bezdek , Gyorgy Kiss

One of the most important problems in Geometric Tomography is to establish properties of a given convex body if we know some properties over its sections or its projections. There are many interesting and deep results that provide…

A common representation of a three dimensional object in computer applications, such as graphics and design, is in the form of a triangular mesh. In many instances, individual or groups of triangles in such representation need to satisfy…

Optimization and Control · Mathematics 2019-04-08 Valentin R. Koch , Hung M. Phan

We continue the study of intersection bodies of polytopes, focusing on the behavior of $IP$ under translations of $P$. We introduce an affine hyperplane arrangement and show that the polynomials describing the boundary of $I(P+t)$ can be…

Metric Geometry · Mathematics 2025-06-02 Marie-Charlotte Brandenburg , Chiara Meroni

Polynomial spaces associated to a convex body $C$ in $({\bf R}^+)^d$ have been the object of recent studies. In this work, we consider polynomial spaces associated to non-convex $C$. We develop some basic pluripotential theory including…

Complex Variables · Mathematics 2021-04-09 N. Levenberg , F. Wielonsky

The purpose of this paper is to study the reflections of a convex body. In particular, we are interested in orthogonal reflections of its sections that can be extended to reflections of the whole body. For this reason, we need to study the…

Metric Geometry · Mathematics 2022-08-08 Jorge L. Arocha , Javier Bracho , Luis Montejano

We address the problem of constructing elliptic polytopes in R^d, which are convex hulls of finitely many two-dimensional ellipses with a common center. Such sets arise in the study of spectral properties of matrices, asymptotics of long…

Numerical Analysis · Mathematics 2021-07-07 Thomas Mejstrik , Vladimir Yu. Protasov

We survey results on the problem of covering the space ${\mathbb R}^n$, or a convex body in it, by translates of a convex body. Our main goal is to present a diverse set of methods. A theorem of Rogers is a central result, according to…

Metric Geometry · Mathematics 2016-03-16 Márton Naszódi