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Related papers: On the volume of projections of the cross-polytope

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We consider two well-known problems: upper bounding the volume of lower dimensional ellipsoids contained in convex bodies given their John ellipsoid, and lower bounding the volume of ellipsoids containing projections of convex bodies given…

Metric Geometry · Mathematics 2025-01-03 René Brandenberg , Florian Grundbacher

We determine the maximal hyperplane sections of the regular $n$-simplex, if the distance of the hyperplane to the centroid is fairly large, i.e. larger than the distance of the centroid to the midpoint of edges. Similar results for the…

Functional Analysis · Mathematics 2020-02-26 Hermann König

Let $\mathbb{B}_p^N$ be the $N$-dimensional unit ball corresponding to the $\ell_p$-norm. For each $N\in\mathbb N$ we sample a uniform random subspace $E_N$ of fixed dimension $m\in\mathbb{N}$ and consider the volume of $\mathbb{B}_p^N$…

Probability · Mathematics 2024-12-23 Joscha Prochno , Christoph Thaele , Philipp Tuchel

In this survey article we will consider universal lower bounds on the volume of a Riemannian manifold, given in terms of the volume of lower dimensional objects (primarily the lengths of geodesics). By `universal' we mean without curvature…

Differential Geometry · Mathematics 2007-05-23 Christopher B. Croke , Mikhail G. Katz

We study the $(n-1)$-dimensional volume of central hyperplane sections of the $n$-dimensional cube $Q_n$. Our main goal is two-fold: first, we provide an alternative, simpler argument for proving that the volume of the section perpendicular…

Metric Geometry · Mathematics 2024-06-25 Gergely Ambrus , Barnabás Gárgyán

We consider a finite volume scheme for the two-dimensional incompressible Navier-Stokes equations. We use a triangular mesh. The unknowns for the velocity and pressure are respectively piecewise constant and affine. We use a projection…

Numerical Analysis · Mathematics 2007-05-23 Sebastien Zimmermann

In $\mathbb{R}^n$, we establish an asymptotically sharp upper bound for the upper Minkowski dimension of $k$-porous sets having holes of certain size near every point in $k$ orthogonal directions at all small scales. This bound tends to…

Classical Analysis and ODEs · Mathematics 2017-01-31 Esa Järvenpää , Maarit Järvenpää , Antti Käenmäki , Ville Suomala

Every convex polygon with $n$ vertices is a linear projection of a higher-dimensional polytope with at most $147\,n^{2/3}$ facets.

Combinatorics · Mathematics 2020-03-03 Yaroslav Shitov

In this paper, we investigate the relationships between the volumes of four convex bodies: the cut polytope, metric polytope, rooted metric polytope, and elliptope, defined on graphs with $n$ vertices. The cut polytope is contained in each…

Discrete Mathematics · Computer Science 2026-04-21 David Avis , Luc Devroye

We give upper bounds for volume of sublevel sets of real polynomials. Our method is to combine a version of global Lojasiewicz inequality with some well known estimate on volume of tubes around real algebraic sets. Some applications to…

Complex Variables · Mathematics 2018-04-18 Nguyen Quang Dieu , Dau Hoang Hung , Tien Son Pham , Hoang Thieu Anh

A new intrinsic volume metric is introduced for the class of convex bodies in $\mathbb{R}^n$. As an application, an inequality is proved for the asymptotic best approximation of the Euclidean unit ball by arbitrarily positioned polytopes…

Metric Geometry · Mathematics 2023-03-15 Florian Besau , Steven Hoehner

The approximability of a convex body is a number which measures the difficulty to approximate that body by polytopes. We prove that twice the approximability is equal to the volume entropy for a Hilbert geometry in dimension two end three…

Metric Geometry · Mathematics 2017-03-01 Constantin Vernicos

Let $(X,\Delta)$ be an $n$-dimensional $\epsilon$-klt log $\QQ$-Fano pair. We give an upper bound for the volume ${\rm Vol}(-(K_X+\Delta))=(-(K_X+\Delta))^n$ when $n=2$ or $n=3$ and $X$ is {$\QQ$-factorial} of $\rho(X)=1$. This bound is…

Algebraic Geometry · Mathematics 2012-04-13 Ching-Jui Lai

Intrinsic volumes are fundamental geometric invariants generalizing volume, surface area, and mean width for convex bodies. We establish a unified Laplace-Grassmannian representation for intrinsic and dual volumes of convex polynomial…

Metric Geometry · Mathematics 2025-11-04 Trí Minh Lê , Khai-Hoan Nguyen-Dang

It is proved that the projection constants of two- and three-dimensional spaces are bounded by $4/3$ and $(1+\sqrt 5)/2$, respectively. These bounds are attained precisely by the spaces whose unit balls are the regular hexagon and…

Functional Analysis · Mathematics 2016-09-06 Hermann König , Nicole Tomczak-Jaegermann

A small polygon is a polygon of unit diameter. The maximal perimeter and the maximal width of a convex small polygon with $n=2^s$ sides are unknown when $s \ge 4$. In this paper, we propose an approach to construct convex small $n$-gons of…

Metric Geometry · Mathematics 2023-06-29 Christian Bingane

We study geometric properties of coordinate projections. Among other results, we show that if a body K in R^n has an "almost extremal" volume ratio, then it has a projection of proportional dimension which is close to the cube. We compare…

Functional Analysis · Mathematics 2016-12-23 S. Mendelson , R. Vershynin

We experimentally study the fundamental problem of computing the volume of a convex polytope given as an intersection of linear inequalities. We implement and evaluate practical randomized algorithms for accurately approximating the…

Computational Geometry · Computer Science 2021-04-26 Ioannis Z. Emiris , Vissarion Fisikopoulos

We consider the computation of the volume of the union of high-dimensional geometric objects. While showing that this problem is #P-hard already for very simple bodies (i.e., axis-parallel boxes), we give a fast FPRAS for all objects where…

Computational Geometry · Computer Science 2010-06-09 Karl Bringmann , Tobias Friedrich

In this note we examine the volume of the convex hull of two congruent copies of a convex body in Euclidean $n$-space, under some subsets of the isometry group of the space. We prove inequalities for this volume if the two bodies are…

Metric Geometry · Mathematics 2013-06-19 Ákos G. Horváth , Z. Lángi
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