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Related papers: On Ball's conjectured Santal\'o type inequality

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We prove that an arbitrary convex body $C \subseteq \mathbf{R}^{n+1} $, whose $ k $-th anisotropic curvature measure (for $ k =0, \ldots , n-1 $) is a multiple constant of the anisotropic perimeter of C, must be a rescaled and translated…

Metric Geometry · Mathematics 2022-04-15 Mario Santilli

Symmetry problems in harmonic analysis are formulated and solved. One of these problems is equivalent to the refined Schiffer's conjecture which was recently proved by the author. Let $k=const>0$ be fixed, $S^2$ be the unit sphere in…

Analysis of PDEs · Mathematics 2019-04-26 Alexander G. Ramm

Let $K$ be a convex body in $\mathbb{R}^n$ with Santal\'o point at 0\. We show that if $K$ has a point on the boundary with positive generalized Gau{\ss} curvature, then the volume product $|K| |K^\circ|$ is not minimal. This means that a…

Functional Analysis · Mathematics 2010-09-21 Shlomo Reisner , Carsten Schütt , Elisabeth M. Werner

A classical theorem of Alon and Milman states that any $d$ dimensional centrally symmetric convex body has a projection of dimension $m\geq e^{c\sqrt{\ln{d}}}$ which is either close to the $m$-dimensional Euclidean ball or to the…

Metric Geometry · Mathematics 2018-05-08 Marton Naszodi

W. Schmidt, H. Montgomery, and J. Beck proved a result on irregularities of distribution with respect to $d$-dimensional balls. In this paper, we extend their result to any $d$-dimensional convex body with a smooth boundary and finite order…

Number Theory · Mathematics 2025-03-04 Luca Brandolini , Leonardo Colzani , Giancarlo Travaglini

In this new version, we give an affirmative solution to a conjecture of Cheng proposed in 1979 which asserts that the Bergman metric of a smoothly bounded strongly pseudoconvex domain in $\mathbb{C}^n, n\geq 2,$ is K\"ahler-Einstein if and…

Complex Variables · Mathematics 2019-07-18 Xiaojun Huang , Ming Xiao

For any convex body $K \subseteq \mathbb R^n$, S. Bubeck and R. Eldan introduced the entropic barrier on $K$ and showed that it is a $(1+o(1)) \, n$-self-concordant barrier. In this note, we observe that the optimal bound of $n$ on the…

Metric Geometry · Mathematics 2021-12-22 Sinho Chewi

For two convex bodies K and T in $R^n$, the covering number of K by T, denoted N(K,T), is defined as the minimal number of translates of T needed to cover K. Let us denote by $K^o$ the polar body of K and by D the euclidean unit ball in…

Functional Analysis · Mathematics 2007-05-23 S. Artstein , V. Milman , S. J. Szarek

In this paper, a new approach of defining Steiner symmetrization of coercive convex functions is proposed and some fundamental properties of the new Steiner symmetrization are proved. Further, using the new Steiner symmetrization, we give a…

Differential Geometry · Mathematics 2014-03-04 Youjiang Lin , Gangsong Leng , Lujun Guo

The three-dimensional symmetric Mahler inequality states that, for every origin-symmetric convex body \(K=-K\subset \mathbb{R}^3\), \[ \VP(K)= |K|\,|K^\circ|\geq \frac{32}{3}. \] It was recently proved by Iriyeh--Shibata \cite{IS2020}, and…

Metric Geometry · Mathematics 2026-05-14 Shibing Chen , Yuanyuan Li , Dongmeng Xi , Zhefeng Xu

We consider a class of elliptic quasivariational inequalities in a reflexive Banach space $X$ for which we recall a convergence criterion obtained in [10]. Each inequality $\cal P$ in the class is governed by a set of constraints $K$ and…

Analysis of PDEs · Mathematics 2024-09-25 Piotr Bartman-Szwarc , Anna Ochal , Mircea Sofonea , Domingo A. Tarzia

A 1972 duality conjecture due to Pietsch asserts that the entropy numbers of a compact operator acting between two Banach spaces and those of its adjoint are (in an appropriate sense) equivalent. This is equivalent to a dimension free…

Functional Analysis · Mathematics 2007-05-23 S. Artstein , V. Milman , S. J. Szarek , N. Tomczak-Jaegermann

A very fundamental geometric problem on finite systems of spheres was independently phrased by Kneser (1955) and Poulsen (1954). According to their well-known conjecture if a finite set of balls in Euclidean space is repositioned so that…

Metric Geometry · Mathematics 2011-09-29 Karoly Bezdek

High proved the following theorem. If the intersections of any two congruent copies of a plane convex body are centrally symmetric, then this body is a circle. In our paper we extend the theorem of High to spherical and hyperbolic planes.…

Metric Geometry · Mathematics 2016-01-19 J. Jerónimo-Castro , E. Makai

Positive solutions of homogeneous Dirichlet boundary value problems or initial-value problems for certain elliptic or parabolic equations must be radially symmetric and monotone in the radial direction if just one of their level surfaces is…

Analysis of PDEs · Mathematics 2013-07-05 Giulio Ciraolo , Rolando Magnanini , Shigeru Sakaguchi

The famous Minkowski inequality provides a sharp lower bound for the mixed volume $V(K,M[n-1])$ of two convex bodies $K,M\subset\mathbb{R}^n$ in terms of powers of the volumes of the individual bodies $K$ and $M$. The special case where $K$…

Metric Geometry · Mathematics 2020-12-04 Daniel Hug , Károly Böröczky

For any origin-symmetric convex body $K$ in $\mathbb{R}^n$ in isotropic position, we obtain the bound: \[ M^*(K) \leq C \sqrt{n} \log(n)^2 L_K ~, \] where $M^*(K)$ denotes (half) the mean-width of $K$, $L_K$ is the isotropic constant of…

Functional Analysis · Mathematics 2014-05-09 Emanuel Milman

In this paper we prove the following Willmore-type inequality: On an unbounded closed convex set $K\subset\mathbb{R}^{n+1}$ $(n\ge 2)$, for any embedded hypersurface $\Sigma\subset K$ with boundary $\partial\Sigma\subset \partial K$…

Differential Geometry · Mathematics 2025-03-06 Xiaohan Jia , Guofang Wang , Chao Xia , Xuwen Zhang

In this note we present the solution of some isoperimetric problems in open convex cones of $\R^n$ in which perimeter and volume are measured with respect to certain nonradial weights. Surprisingly, Euclidean balls centered at the origin…

Analysis of PDEs · Mathematics 2012-10-10 Xavier Cabre , Xavier Ros-Oton , Joaquim Serra

We review the theory of intrinsic geometry of convex surfaces in the Euclidean space and prove the following theorem: if the surface of a convex body K contains arbitrary long closed simple geodesics, then K is an isosceles tetrahedron.

Differential Geometry · Mathematics 2018-10-01 Arseniy Akopyan , Anton Petrunin