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In this work we consider the problem of finding the minimum-weight loop cover of an undirected graph. This combinatorial optimization problem is called 2-matching and can be seen as a relaxation of the traveling salesman problem since one…

Disordered Systems and Neural Networks · Physics 2018-08-28 Sergio Caracciolo , Andrea Di Gioacchino , Enrico M. Malatesta

Coverings of convex bodies have emerged as a central component in the design of efficient solutions to approximation problems involving convex bodies. Intuitively, given a convex body $K$ and $\epsilon> 0$, a covering is a collection of…

Computational Geometry · Computer Science 2023-03-16 Sunil Arya , Guilherme D. da Fonseca , David M. Mount

We explore the separability of point sets in the plane by a restricted-orientation convex hull, which is an orientation-dependent, possibly disconnected, and non-convex enclosing shape that generalizes the convex hull. Let $R$ and $B$ be…

Computational Geometry · Computer Science 2022-09-12 Carlos Alegría , David Orden , Carlos Seara , Jorge Urrutia

We prove that geodesic balls centered at some base point are isoperimetric in the real hyperbolic space $H_{\mathbb R}^n$ endowed with a smooth, radial, strictly log-convex density on the volume and perimeter. This is an analogue of the…

Differential Geometry · Mathematics 2022-09-26 Lauro Silini

We consider the class of $\lambda$-concave bodies in $\mathbb R^{n+1}$; that is, convex bodies with the property that each of their boundary points supports a tangent ball of radius $1/\lambda$ that lies locally (around the boundary point)…

Differential Geometry · Mathematics 2019-07-22 Roman Chernov , Kostiantyn Drach , Kateryna Tatarko

We explore separable property of the joint numerical range $G(\Bbb R^n)$ of a special class of quadratic functions and apply it to solving the smallest enclosing ball (SEB) problem which asks to find a ball $B(a,r)$ in $\Bbb R^n$ with…

Optimization and Control · Mathematics 2025-10-21 Van-Bong Nguyen , Huu-Quang Nguyen

With the goal of obtaining strong relaxations for binary polynomial optimization problems, we introduce the pseudo-Boolean polytope defined as the convex hull of the set of binary points satisfying a collection of equations containing…

Optimization and Control · Mathematics 2024-07-02 Alberto Del Pia , Aida Khajavirad

Systems of identical particles with equal charge are studied under a special type of confinement. These classical particles are free to move inside some convex region S and on the boundary of it $\Omega$ (the $S^{d-1}-$ sphere, in our…

Classical Physics · Physics 2016-11-25 J. Batle

In this work we study the geodesic structure of the space $\Sigma (X)$ of compact balls of a complete and locally compact metric length space endowed with the Hausdorff distance $d_H$. In particular, we focus on a geometric condition…

Metric Geometry · Mathematics 2019-09-20 Waldemar Barrera , Luis Montes de Oca , Didier A. Solis

We give an overview of the 2024 Computational Geometry Challenge targeting the problem \textsc{Maximum Polygon Packing}: Given a convex region $P$ in the plane, and a collection of simple polygons $Q_1, \ldots, Q_n$, each $Q_i$ with a…

Computational Geometry · Computer Science 2024-03-26 Sándor P. Fekete , Phillip Keldenich , Dominik Krupke , Stefan Schirra

We determine the homeomorphism type of the hyperspace of positively curved $C^\infty$ convex bodies in $\mathbb R^n$, and derive various properties of its quotient by the group of Euclidean isometries. We make a systematic study of…

General Topology · Mathematics 2017-06-08 Igor Belegradek

In this paper we discuss a couple of observations related to polynomial convexity. More precisely, (i) We observe that the union of finitely many disjoint closed balls with centres in $\cup_{\theta\in[0,\pi/2]}e^{i\theta}V$ is polynomially…

Complex Variables · Mathematics 2019-09-11 Sushil Gorai

For a given $\lambda >0$, a convex body in $\mathbb R^n$ is $\lambda$-convex if it is the intersection of (finitely or infinitely many) balls of radius $1/\lambda$. In this note, we show that among all $\lambda$-convex bodies in $\mathbb…

Metric Geometry · Mathematics 2025-11-18 Kostiantyn Drach , Kateryna Tatarko

We consider the moments of the volume of the symmetric convex hull of independent random points in an $n$-dimensional symmetric convex body. We calculate explicitly the second and fourth moments for $n$ points when the given body is $B_q^n$…

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

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…

Metric Geometry · Mathematics 2017-03-30 Marek Lassak

Geodesic orbit spaces (or g.o. spaces) are defined as those homogeneous Riemannian spaces $(M=G/H,g)$ whose geodesics are orbits of one-parameter subgroups of $G$. The corresponding metric $g$ is called a geodesic orbit metric. We study the…

Differential Geometry · Mathematics 2021-04-20 Andreas Arvanitoyeorgos , Nikolaos Panagiotis Souris , Marina Statha

We prove that if $C$ is a symmetric convex body of revolution in $\mathbb R^4$ containing the unit Euclidean ball $\mathbb B_4$, such that the sections of $C$ by hyperplanes tangent to $\mathbb B_4$ have constant area $A>0$, then $C$ is a…

Metric Geometry · Mathematics 2026-05-04 J. Haddad , D. Ryabogin

In this paper, we characterize the closures of convex hulls of unitary orbits of self-adjoint operators in unital, separable, simple C$^*$-algebras with non-trivial tracial simplex, real rank zero, stable rank one, and strict comparison of…

Operator Algebras · Mathematics 2019-02-08 Ping Wong Ng , Paul Skoufranis

We define certain natural finite sums of $n$'th roots of unity, called $G_P(n)$, that are associated to each convex integer polytope $P$, and which generalize the classical $1$-dimensional Gauss sum $G(n)$ defined over $\mathbb Z/ {n…

Number Theory · Mathematics 2020-05-04 Romanos-Diogenes Malikiosis , Sinai Robins , Yichi Zhang

We study the class of (locally) anti-blocking bodies as well as some associated classes of convex bodies. For these bodies, we prove geometric inequalities regarding volumes and mixed volumes, including Godberson's conjecture, near-optimal…

Metric Geometry · Mathematics 2022-01-14 Shiri Artstein-Avidan , Shay Sadovsky , Raman Sanyal