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Related papers: A generalization of Gr\"unbaum's inequality

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We establish a general criterion for the validity of inequalities of the following form: A certain convex combination of the values of a convex function at n points and of its value at a weighted mean of these n points is always greater or…

Functional Analysis · Mathematics 2008-03-21 Darij Grinberg

The classical Loomis-Whitney inequality and the uniform cover inequality of Bollob\'{a}s and Thomason provide lower bounds for the volume of a compact set in terms of its lower dimensional coordinate projections. We provide further…

Metric Geometry · Mathematics 2016-06-14 S. Brazitikos , A. Giannopoulos , D-M. Liakopoulos

We construct a convex body $K$ in $\mathbb{R}^n$, $n \geq 5$, with the property that there is exactly one hyperplane $H$ passing through $c(K)$, the centroid of $K$, such that the centroid of $K\cap H$ coincides with $c(K)$. This provides…

Metric Geometry · Mathematics 2024-11-11 S. Myroshnychenko , K. Tatarko , V. Yaskin

An affine version of the linear subspace concentration inequality as proposed by Wu is established for centered convex bodies. This generalizes results from Wu and Freyer, Henk, Kipp on polytopes to convex bodies.

Metric Geometry · Mathematics 2024-09-24 Katharina Eller , Ansgar Freyer

The purpose of this paper is twofold. In the first part we concentrate on hyperplane sections of algebraic schemes, and present results for determining when Gr\"obner bases pass to the quotient and when they can be lifted. The main…

Commutative Algebra · Mathematics 2014-06-24 Lorenzo Robbiano

Let $\partial \,\mathcal{C}$ be the boundary of a compact convex body $\mathcal{C}$ in $\mathbb{R}^n,\, n\geq 2$, and $O$ be an interior point of $\mathcal C$. Every straight line $l$ containing $O$ cuts from $\mathcal{C}$ a segment $[AB]$…

Metric Geometry · Mathematics 2025-06-10 Petar Kenderov , Oleg Mushkarov , Nikolai Nikolov

In a given hypercube, draw grid lines parallel to the edges, and consider all hypercuboids (or hypercubes) whose edges are lying on the grid lines or the boundary. We find the limit of the value of the ratio of the arithmetic mean of the…

Combinatorics · Mathematics 2025-01-03 Takashi Hirotsu

A $\sqrt{n}$ estimate in the hyperplane problem with arbitrary measures has recently been proved in \cite{K3}. In this note we present analogs of this result for sections of lower dimensions and in the complex case. We deduce these…

Metric Geometry · Mathematics 2013-09-26 Alexander Koldobsky

We state a general formula to compute the volume of the intersection of the regular $n$-simplex with some $k$-dimensional subspace. It is known that for central hyperplanes the one through the centroid containing $n-1$ vertices gives the…

Metric Geometry · Mathematics 2019-11-21 Hauke Dirksen

We prove a conjecture of B. Gr\"unbaum stating that the set of affine invariant points of a convex body equals to the set of points invariant under all affine linear symmetries of the convex body. As a consequence we give a short proof on…

Metric Geometry · Mathematics 2017-09-11 Olaf Mordhorst

We give a B\'ezout type inequality for mixed volumes, which holds true for any convex bodies. The key ingredient is the reverse Khovanskii-Teissier inequality for convex bodies, which was obtained in our previous work and inspired by its…

Algebraic Geometry · Mathematics 2017-04-05 Jian Xiao

Let $V$ be a symmetric convex body in $\R^m$. We prove sharp Bernstein-type inequalities for entire functions of exponential type with the spectrum in $V$ and discuss certain properties of the extremal functions. Markov-type inequalities…

Classical Analysis and ODEs · Mathematics 2022-12-26 Michael I. Ganzburg

We provide a sharp lower bound for the perimeter of the inner parallel sets of a convex body $\Omega$. The bound depends only on the perimeter and inradius $r$ of the original body and states that \[|\partial\Omega_t| \geq…

Metric Geometry · Mathematics 2020-05-05 Simon Larson

Using combinatorial methods, we derive several formulas for the volume of convex bodies obtained by intersecting a unit hypercube with a halfspace, or with a hyperplane of codimension 1, or with a flat defined by two parallel hyperplanes.…

Metric Geometry · Mathematics 2008-02-12 Jean-Luc Marichal , Michael J. Mossinghoff

In this article, we obtain two interesting general inequalities concerning Riemman sums of convex functions, which in particular, sharpen Alzer's inequality and give a suitable converse for it.

Classical Analysis and ODEs · Mathematics 2007-10-22 Jamal Rooin

We aim to study the classical Rosenthal-Szasz inequality for a plane whose geometry is given by a norm. This inequality states that the bodies of constant width have the largest perimeter among all planar convex bodies of given diameter. In…

Metric Geometry · Mathematics 2018-05-29 Vitor Balestro , Horst Martini

We make a careful analysis of Bohr's inequality, in the line started by Kayumov and Ponnusamy, where some extra summand (depending on the function) is added in the right-hand side of the inequality. We analyse the inequality when smaller…

Complex Variables · Mathematics 2024-09-27 Mario Guillén , Pablo Sevilla-Peris

The long-standing Godbersen's conjecture asserts that the Rogers-Shephard inequality for the volume of the difference body is refined by an inequality for the mixed volume of a convex body and its reflection about the origin. The conjecture…

Metric Geometry · Mathematics 2025-10-30 Jan Kotrbatý

We prove sharp inequalities for the average number of affine diameters through the points of a convex body $K$ in ${\mathbb R}^n$. These inequalities hold if $K$ is either a polytope or of dimension two. An example shows that the proof…

Metric Geometry · Mathematics 2014-05-08 Imre Barany , Daniel Hug , Rolf Schneider

The purpose of this paper is to answer the following question: If all hyperplane sections through the origin of a convex body are "equal", is the convex body "equal" to the ball? The meaning of the notion "equal" will change in the course…

Metric Geometry · Mathematics 2021-09-20 Luis Montejano