English
Related papers

Related papers: Projection theorems for intermediate dimensions

200 papers

We present several applications of the Assouad dimension, and the related quasi-Assouad dimension and Assouad spectrum, to the box and packing dimensions of orthogonal projections of sets. For example, we show that if the (quasi-)Assouad…

Metric Geometry · Mathematics 2021-07-02 Kenneth J. Falconer , Jonathan M. Fraser , Pablo Shmerkin

This writeup describes ongoing work on designing and testing a certain family of correspondences between compact metric spaces that we call \emph{embedding-projection correspondences} (EPCs). Of particular interest are EPCs between spheres…

Metric Geometry · Mathematics 2024-07-04 Facundo Mémoli , Zane T. Smith

We study a wide class of fractal interpolation functions in a single platform by considering the domains of these functions as general attractors. We obtain lower and upper bounds of the box dimension of these functions in a more general…

Dynamical Systems · Mathematics 2024-10-07 R. Pasupathi

We show that the family of $m$-dimensional isotropic projections in $\R^{2n}$ is transversal. As an application we show that the Besicovitch-Federer projection theorem holds for isotropic projections. We also use transversality to obtain…

Classical Analysis and ODEs · Mathematics 2012-05-15 Risto Hovila

The interstellar medium seems to have an underlying fractal structure which can be characterized through its fractal dimension. However, interstellar clouds are observed as projected two-dimensional images, and the projection of a…

Astrophysics · Physics 2007-05-23 Nestor Sanchez , Emilio J. Alfaro , Enrique Perez

We describe some recent results on the dimensions of linear projections of self-affine fractals, focusing in particular on an upper bound for the dimension of the projected image. We give a self-contained treatment of this bound and…

Dynamical Systems · Mathematics 2025-03-11 Ian D. Morris

In this work, we aim to advance the development of a fractal theory for sets of integers. The core idea is to utilize the fractal structure of $p$-adic integers, where $p$ is a prime number, and compare this with conventional densities and…

Number Theory · Mathematics 2024-08-07 Davi Lima , Alex Zamudio Espinosa

We introduce a new concept of dimension for metric spaces, the so-called topological Hausdorff dimension. It is defined by a very natural combination of the definitions of the topological dimension and the Hausdorff dimension. The value of…

Classical Analysis and ODEs · Mathematics 2015-04-21 Richárd Balka , Zoltán Buczolich , Márton Elekes

Using geometric inversion with respect to the origin we extend the definition of box dimension to the case of unbounded subsets of Euclidean spaces. Alternative but equivalent definition is provided using stereographic projection on the…

Dynamical Systems · Mathematics 2015-02-11 Goran Radunović , Vesna Županović , Darko Žubrinić

Let $\gamma: [-1, 1]\to \mathbb{R}^n$ be a smooth curve that is non-degenerate. Take $m\le n$ and a Borel set $E\subset [0, 1]^n$. We prove that the orthogonal projection of $E$ to the $m$-th order tangent space of $\gamma$ at $\theta\in…

Classical Analysis and ODEs · Mathematics 2024-01-23 Shengwen Gan , Shaoming Guo , Hong Wang

For any $x\in\mathbb{R}^d$, $d\geq 2$, denote $\pi^x: \mathbb{R}^d\backslash\{x\}\rightarrow S^{d-1}$ as the radial projection $$\pi^x(y)=\frac{y-x}{|y-x|}. $$ Given a Borel set $E\subset{\Bbb R}^d$, $\dim_{\mathcal{H}} E\leq d-1$, in this…

Classical Analysis and ODEs · Mathematics 2019-04-04 Bochen Liu

We consider several classical results related to the Hausdorff dimension of exceptional sets of orthogonal projections and try to find out whether they have reasonable formulations in terms of packing dimension. We also investigate the…

Classical Analysis and ODEs · Mathematics 2015-05-19 Tuomas Orponen

We review the motivation and fundamental properties of the Hausdorff dimension of metric spaces and illustrate this with a number of examples, some of which are expected and well-known. We also give examples where the Hausdorff dimension…

Dynamical Systems · Mathematics 2007-08-21 Dierk Schleicher

For Borel subsets A and B of the Euclidean n-space the intersection of A with generic rotations and translations of B has often Hausdorff dimension at least dim A + dim B - n. Estimates for the exceptional set of rotations are derived.

Metric Geometry · Mathematics 2018-01-03 Pertti Mattila

The main goal of this paper has a double purpose. On the one hand, we propose a new definition in order to compute the fractal dimension of a subset respect to any fractal structure, which completes the theory of classical box-counting…

Chaotic Dynamics · Physics 2010-07-23 M. Fernández-Martínez , M. A Sánchez-Granero

We provide exposition into the field of projection theory, which lies at the intersection of incidence geometry and geometric measure theory. We first give the necessary preliminaries in Chapter 2, focusing on incidences between points and…

Classical Analysis and ODEs · Mathematics 2025-09-30 Paige Bright

Mesoscale structures can often be described as fractional dimensional across a wide range of scales. We consider a $\gamma$ dimensional measure embedded in an $N$ dimensional space and discuss how to determine its dimension, both in $N$…

High Energy Astrophysical Phenomena · Physics 2025-12-09 Svitlana Mayboroda , David N Spergel

Let $\ell_1,\ell_2,\dots$ be a countable collection of lines in ${\mathbb R}^d$. For any $t \in [0,1]$ we construct a compact set $\Gamma\subset{\mathbb R}^d$ with Hausdorff dimension $d-1+t$ which projects injectively into each $\ell_i$,…

Metric Geometry · Mathematics 2021-08-25 Frank Coen , Nate Gillman , Tamás Keleti , Dylan King , Jennifer Zhu

We present strong versions of Marstrand's projection theorems and other related theorems. For example, if E is a plane set of positive and finite s-dimensional Hausdorff measure, there is a set X of directions of Lebesgue measure 0, such…

Metric Geometry · Mathematics 2015-11-19 Kenneth Falconer , Pertti Mattila

We study projections onto non-degenerate one-dimensional families of lines and planes in $\mathbb{R}^{3}$. Using the classical potential theoretic approach of R. Kaufman, one can show that the Hausdorff dimension of at most…

Classical Analysis and ODEs · Mathematics 2014-11-27 Katrin Fässler , Tuomas Orponen