English
Related papers

Related papers: Retrieving convex bodies from restricted covariogr…

200 papers

We prove Gaussian approximation theorems for specific $k$-dimensional marginals of convex bodies which possess certain symmetries. In particular, we treat bodies which possess a 1-unconditional basis, as well as simplices. Our results…

Metric Geometry · Mathematics 2009-01-09 Mark W. Meckes

We give the sharp lower bound of the volume product of $n$-dimensional convex bodies which are invariant under a discrete subgroup $SO(K)=\{ g \in SO(n); g(K)=K \}$, where $K$ is an $n$-cube or $n$-simplex. This provides new partial results…

Metric Geometry · Mathematics 2022-03-29 Hiroshi Iriyeh , Masataka Shibata

We study the volume ratio between projections of two convex bodies. Given a high-dimensional convex body $K$ we show that there is another convex body $L$ such that the volume ratio between any two projections of fixed rank of the bodies…

Metric Geometry · Mathematics 2022-11-14 Daniel Galicer , Alexander E. Litvak , Mariano Merzbacher , Damián Pinasco

For a convex body $K\subset\R^n$ and $i\in\{1,...,n-1\}$, the function assigning to any $i$-dimensional subspace $L$ of $\R^n$, the $i$-dimensional volume of the orthogonal projection of $K$ to $L$, is called the $i$-th projection function…

Metric Geometry · Mathematics 2007-05-23 Ralph Howard , Daniel Hug

The average section functional ${\rm as}(K)$ of a centered convex body in ${\mathbb R}^n$ is the average volume of central hyperplane sections of $K$: \begin{equation*}{\rm as}(K)=\int_{S^{n-1}}|K\cap \xi^{\perp }|\,d\sigma (\xi…

Metric Geometry · Mathematics 2016-07-19 Silouanos Brazitikos , Susanna Dann , Apostolos Giannopoulos , Alexander Koldobsky

A convex body K has associated with it a unique circumscribed ellipsoid CE(K) with minimum volume, and a unique inscribed ellipsoid IE(K) with maximum volume. We first give a unified, modern exposition of the basic theory of these extremal…

Metric Geometry · Mathematics 2007-09-06 Osman Güler , Filiz Gürtuna

Let $K$ be a $d$ dimensional convex body with a twice continuously differentiable boundary and everywhere positive Gauss-Kronecker curvature. Denote by $K_n$ the convex hull of $n$ points chosen randomly and independently from $K$ according…

Metric Geometry · Mathematics 2015-02-25 Imre Bárány , Ferenc Fodor , Viktor Vígh

It is proved that if $u_1,\ldots, u_n$ are vectors in ${\Bbb R}^k, k\le n, 1 \le p < \infty$ and $$r = ({1\over k} \sum ^n_1 |u_i|^p)^{1\over p}$$ then the volume of the symmetric convex body whose boundary functionals are $\pm u_1,\ldots,…

Metric Geometry · Mathematics 2016-09-06 Keith Ball , Alain Pajor

In convex geometry, the constructions that assign to a convex body its difference body, projection body, or volume have the following properties: They are (1) invariant under volume-preserving linear changes of coordinates; (2) continuous;…

Metric Geometry · Mathematics 2024-02-12 Jakob Henkel , Thomas Wannerer

We study isomorphic properties of two generalizations of intersection bodies, the class of k-intersection bodies and the class of generalized k-intersection bodies. We also show that the Banach-Mazur distance of the k-intersection body of a…

Functional Analysis · Mathematics 2011-05-16 A. Koldobsky , G. Paouris , M. Zymonopoulou

We investigate algorithms for reconstructing a convex body $K$ in $\mathbb {R}^n$ from noisy measurements of its support function or its brightness function in $k$ directions $u_1,...,u_k$. The key idea of these algorithms is to construct a…

Statistics Theory · Mathematics 2007-06-13 Richard J. Gardner , Markus Kiderlen , Peyman Milanfar

Let $K$ be a convex body in $\mathbb R^n$. We prove that in small codimensions, the sections of a convex body through the centroid are quite symmetric with respect to volume. As a consequence of our estimates we give a positive answer to a…

Metric Geometry · Mathematics 2016-04-20 Matthieu Fradelizi , Mathieu Meyer , Vlad Yaskin

We show that, for any prime power n and any convex body K (i.e., a compact convex set with interior) in Rd, there exists a partition of K into n convex sets with equal volumes and equal surface areas. Similar results regarding…

Metric Geometry · Mathematics 2017-05-09 Roman Karasev , Alfredo Hubard , Boris Aronov

This paper concerns the characterisation of second order marginals for random sets in a discrete setting. Under the instance of unit covariances, this problem possesses a combinatorial symmetry, exploited jointly in the companion paper to…

Probability · Mathematics 2013-01-21 Raphael Lachieze-Rey

We prove that for every convex body $K$ with the center of mass at the origin and every $\varepsilon\in \left(0,\frac{1}{2}\right)$, there exists a convex polytope $P$ with at most $e^{O(d)}\varepsilon^{-\frac{d-1}{2}}$ vertices such that…

Classical Analysis and ODEs · Mathematics 2017-05-05 Márton Naszódi , Fedor Nazarov , Dmitry Ryabogin

The "old-new" concept of convex-hull function was investigated by several authors in the last seventy years. A recent research on it led to some other volume functions as the covariogram function, the widthness function or the so-called…

Metric Geometry · Mathematics 2019-08-09 Ákos G. Horváth

Let K be a convex body in $R^d$. A random polytope is the convex hull $[x_1,...,x_n]$ of finitely many points chosen at random in K. $\Bbb E(K,n)$ is the expectation of the volume of a random polytope of n randomly chosen points. I.…

Metric Geometry · Mathematics 2016-09-06 Carsten Schütt

Let $K \subset {\mathbb R}^2$ be an $o$-symmetric convex body, and $K^*$ its polar body. Then we have $|K|\cdot |K^*| \ge 8$, with equality if and only if $K$ is a parallelogram. ($| \cdot |$ denotes volume). If $K \subset {\mathbb R}^2$ is…

Metric Geometry · Mathematics 2015-07-07 K. J. Böröczky , E. Makai , M. Meyer , S. Reisner

In the paper we investigate the continuity properties of the mapping $\Phi$ which sends any non-empty compact connected hv-convex planar set $K$ to the associated generalized conic function $f_K$. The function $f_K$ measures the average…

Metric Geometry · Mathematics 2013-12-23 Csaba Vincze , Ábris Nagy

We present an alternative approach to some results of Koldobsky on measures of sections of symmetric convex bodies, which allows us to extend them to the not necessarily symmetric setting. We prove that if $K$ is a convex body in ${\mathbb…

Metric Geometry · Mathematics 2015-12-31 Giorgos Chasapis , Apostolos Giannopoulos , Dimitris-Marios Liakopoulos