English
Related papers

Related papers: When is a Minkowski norm strictly sub-convex?

200 papers

We prove three results in this paper. First, we prove for a wide class of functions $\varphi\in C^2(\mathbb{S}^{n-1})$ and $\psi(X, \nu)\in C^2(\mathbb{R}^{n+1}\times\mathbb{H}^n),$ there exists a unique, entire, strictly convex, spacelike…

Differential Geometry · Mathematics 2024-02-14 Changyu Ren , Zhizhang Wang , Ling Xiao

Here is one of the results obtained in this paper: Let $X, Y$ be two convex sets each in a real vector space, let $J:X\times Y\to {\bf R}$ be convex and without global minima in $X$ and concave in $Y$, and let $\Phi:X\to {\bf R}$ be…

Optimization and Control · Mathematics 2019-09-19 Biagio Ricceri

It is well-known that the cross covariogram of two convex bodies in n dimensions is 1/n-concave on its support. This paper provides conditions for strict 1/n-concavity in dimension n>1, and an analysis of how it can fail. Among the…

Metric Geometry · Mathematics 2025-08-07 Gabriele Bianchi , Almut Burchard , Lawrence Lin

Given a continuous real-valued function on [0, 1], and a closed subset E \subset [0, 1] we denote by f E the restriction of f to E, that is, the function defined only on E that takes the same values as f at every point of E >. The…

Classical Analysis and ODEs · Mathematics 2007-11-29 Jean-Pierre Kahane , Yitzhak Katznelson

Given a compact convex domain $C\subset \mathbb{R}^k$ and bounded measurable functions $f_1,\ldots,f_n:C\to \mathbb{R}$, define the sup-convolution $(f_1\ast \ldots \ast f_n)(z)$ to be the supremum average value of…

Functional Analysis · Mathematics 2023-07-20 Peter van Hintum , Hunter Spink , Marius Tiba

The Minkowski inequality is a classical inequality in differential geometry, giving a bound from below, on the total mean curvature of a convex surface in Euclidean space, in terms of its area. Recently there has been interest in proving…

Differential Geometry · Mathematics 2018-06-28 Stephen McCormick

Motivated by the well-known implications among $t$-convexity properties of real functions, analogous relations among the upper and lower $M$-convexity properties of real functions are established. More precisely, having an $n$-tuple…

Classical Analysis and ODEs · Mathematics 2017-06-29 Tibor Kiss , Zsolt Páles

We establish the following max-plus analogue of Minkowski's theorem. Any point of a compact max-plus convex subset of $(R\cup\{-\infty\})^n$ can be written as the max-plus convex combination of at most $n+1$ of the extreme points of this…

Metric Geometry · Mathematics 2007-05-23 Stephane Gaubert , Ricardo Katz

The Shapley-Folkman theorem shows that Minkowski averages of uniformly bounded sets tend to be convex when the number of terms in the sum becomes much larger than the ambient dimension. In optimization, Aubin and Ekeland [1976] show that…

Optimization and Control · Mathematics 2019-07-02 Thomas Kerdreux , Igor Colin , Alexandre d'Aspremont

For a Minkowski centered convex compact set $K$ we define $\alpha(K)$ to be the smallest possible factor to cover $K \cap (-K)$ by a rescalation of $\mathrm{conv} (K\cup (-K))$ and give a complete description of the possible values of…

Metric Geometry · Mathematics 2024-01-29 René Brandenberg , Katherina von Dichter , Bernardo González Merino

Let $V\subset\R^m$ be a centrally symmetric convex body and let $V^*\subset\R^m$ be its polar. We prove limit relations between the sharp constants in the multivariate Markov-Bernstein-Nikolskii type inequalities for algebraic polynomials…

Classical Analysis and ODEs · Mathematics 2020-02-27 Michael I. Ganzburg

We establish a maximum principle for a two-point function in order to analyze the convexity of level sets of harmonic functions. We show that this can be used to prove a strict convexity result involving the smallest principal curvature of…

Analysis of PDEs · Mathematics 2018-04-25 Ben Weinkove

In this paper we consider Riemannian manifolds of dimension at least $3$, with nonnegative Ricci curvature and Euclidean Volume Growth. For every open bounded subset with smooth boundary we establish the validity of an optimal Minkowski…

Differential Geometry · Mathematics 2024-11-06 Luca Benatti , Mattia Fogagnolo , Lorenzo Mazzieri

The aim of this paper is twofold. On one hand the generalized Minkowski sets are defined and characterized. On the other hand, the Motzkin decomposable sets, along with their epigraphic versions are considered and characterized in new ways.…

Optimization and Control · Mathematics 2023-01-24 Juan Enrique Martínez-Legaz , Cornel Pintea

This article derives closed-form parametric formulas for the Minkowski sums of convex bodies in d-dimensional Euclidean space with boundaries that are smooth and have all positive sectional curvatures at every point. Under these conditions,…

Metric Geometry · Mathematics 2021-11-04 Sipu Ruan , Gregory S. Chirikjian

A relatively polynomially convex subset $V$ of a domain $\Omega$ has the extension property if for every polynomial $p$ there is a bounded holomorphic function $\phi$ on $\Omega$ that agrees with $p$ on $V$ and whose $H^\infty$ norm on…

Complex Variables · Mathematics 2017-04-13 Lukasz Kosinski , John McCarthy

A differentiable function is pseudoconvex if and only if its restrictions over straight lines are pseudoconvex. A differentiable function depending on one variable, defined on some closed interval $[a,b]$ is pseudoconvex if and only if…

Optimization and Control · Mathematics 2019-11-19 Vsevolod Ivanov Ivanov

We prove four results towards a description, in terms of the null support function, of the set of isometric embeddings of the hyperbolic plane into Minkowski 3-space. We show that for sufficiently tame null support function, the…

Differential Geometry · Mathematics 2022-07-21 Francesco Bonsante , Andrea Seppi , Peter Smillie

The Minkowski problem for a class of unbounded closed convex sets is considered. This is equivalent to a Monge-Amp\`ere equation on a bounded convex open domain with possibly non-integrable given data. A complete solution (necessary and…

Metric Geometry · Mathematics 2025-05-01 Vadim Semenov , Yiming Zhao

Let $V$ be a finite nonempty set. A transit function is a map $R:V\times V\rightarrow 2^V$ such that $R(u,u)=\{u\}$, $R(u,v)=R(v,u)$ and $u\in R(u,v)$ hold for every $u,v\in V$. A set $K\subseteq V$ is $R$-convex if $R(u,v)\subset K$ for…

Combinatorics · Mathematics 2024-06-04 Manoj Changat , Lekshmi Kamal K. Sheela , Iztok Peterin , Ameera Vaheeda Shanavas