English
Related papers

Related papers: Strong Marstrand theorems and dimensions of sets f…

200 papers

We investigate variants of Marstrand's projection theorem that hold for sets of directions and classes of sets in $\mathbb{R}^2$. We say that a set of directions $D \subseteq\mathcal{S}^1$ is $\textit{universal}$ for a class of sets if, for…

Classical Analysis and ODEs · Mathematics 2025-03-25 Jacob B. Fiedler , D. M. Stull

In a paper from 1954 Marstrand proved that if K is a Borel subset of the plane with Hausdorff dimension greater than 1, then its one-dimensional projection has positive Lebesgue measure for almost-all directions. In this article, we give a…

Dynamical Systems · Mathematics 2020-04-21 Yuri Lima , Carlos Gustavo Moreira

In a paper from 1954, Marstrand proved that if $K\subset \mathbb{R}^2$ with Hausdorff dimension greater than 1, then its one-dimensional projection has positive Lebesgue measure for almost-all directions. In this article, we show that if…

Differential Geometry · Mathematics 2014-02-21 Sergio Augusto Romaña Ibarra

We prove that most one-dimensional projections of a discrete subset of a plane are either dense in R (the real line), or form a discrete subset of R. More precisely, the set E of exceptional directions (for which the indicated dichotomy…

Metric Geometry · Mathematics 2012-03-06 Michael Boshernitzan

Assuming $V=L$, we construct a plane set $E$ of Hausdorff dimension $1$ whose every orthogonal projection onto straight lines through the origin has Hausdorff dimension $0$. This is a counterexample to J. M. Marstrand's seminal projection…

Logic · Mathematics 2023-01-18 Linus Richter

Let $1 \leq m < s \leq n$ and let $A \subseteq \mathbb{R}^n$ be a Borel set of with $s$-dimensional Hausdorff measure $\mathcal{H}^s(A) > 0$. The classical Marstrand slicing theorem states that, for almost every $m$-dimensional subspace $V…

Classical Analysis and ODEs · Mathematics 2025-10-14 Ryan E. G. Bushling

Marstrand's celebrated projection theorem gives the Hausdorff dimension of the orthogonal projection of a Borel set in Euclidean space for almost all orthogonal projections. It is straightforward to see that sets for which the Fourier and…

Classical Analysis and ODEs · Mathematics 2024-06-21 Jonathan M. Fraser , Ana E. de Orellana

In 1954 Marstrand proved that if K is a subset of R^2 with Hausdorff dimension greater than 1, then its one-dimensional projection has positive Lebesgue measure for almost-all directions. In this article, we give a combinatorial proof of…

Dynamical Systems · Mathematics 2020-04-21 Yuri Lima , Carlos Gustavo Moreira

We establish a refinement of Marstrand's projection theorem for Hausdorff dimension functions finer than the usual power functions, including an analogue of Marstrand's Theorem for logarithmic Hausdorff dimension.

Metric Geometry · Mathematics 2018-12-17 Victor Beresnevich , Kenneth Falconer , Sanju Velani , Agamemnon Zafeiropoulos

We propose a counting dimension for subsets of Z and prove that, under certain conditions on two such subsets E and F, for Lebesgue almost every real \lambda\ the counting dimension of E+[\lambda F] is at least the minimum between 1 and the…

Dynamical Systems · Mathematics 2020-04-21 Yuri Lima , Carlos Gustavo Moreira

In this paper we use the theory of computing to study fractal dimensions of projections in Euclidean spaces. A fundamental result in fractal geometry is Marstrand's projection theorem, which shows that for every analytic set E, for almost…

Computational Complexity · Computer Science 2021-11-15 Neil Lutz , D. M. Stull

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

We give conditions on a general family $P_{\lambda}:\R^n\to\R^m, \lambda \in \Lambda,$ of orthogonal projections which guarantee that the Hausdorff dimension formula $\dim A\cap P_{\lambda}^{-1}\{u\}=s-m$ holds generically for measurable…

Classical Analysis and ODEs · Mathematics 2020-06-09 Pertti Mattila

This paper extends some results of [M5] and [M3], in particular, removing assumptions of positive lower density. We give conditions on a general family $P_{\lambda}:\mathbb{R}^{n}\to\mathbb{R}^{m}, \lambda \in \Lambda,$ of orthogonal…

Classical Analysis and ODEs · Mathematics 2023-10-12 Pertti Mattila

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

This paper contains new results on two classical topics in fractal geometry: projections, and intersections with affine planes. To keep the notation of the abstract simple, we restrict the discussion to the planar cases of our theorems. Our…

Classical Analysis and ODEs · Mathematics 2016-07-27 Pertti Mattila , Tuomas Orponen

Marstrand's projection theorem from $1954$ states that if $K \subset \mathbb{R}^{3}$ is an analytic set, then, for $\mathcal{H}^{2}$ almost every $e \in S^{2}$, the orthogonal projection $\pi_{e}(K)$ of $K$ to the line spanned by $e$ has…

Classical Analysis and ODEs · Mathematics 2021-07-05 Antti Käenmäki , Tuomas Orponen , Laura Venieri

Let $0 \leq s \leq 1$ and $0 \leq t \leq 2$. An $(s,t)$-Furstenberg set is a set $K \subset \mathbb{R}^{2}$ with the following property: there exists a line set $\mathcal{L}$ of Hausdorff dimension $\dim_{\mathrm{H}} \mathcal{L} \geq t$…

Classical Analysis and ODEs · Mathematics 2025-03-31 Tuomas Orponen , Pablo Shmerkin

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

The macroscopic Hausdorff dimension Dim H (E) of a set E $\subset$ R d was introduced by Barlow and Taylor to quantify a "fractal at large scales" behavior of unbounded, possibly discrete, sets E. We develop a method based on potential…

Classical Analysis and ODEs · Mathematics 2022-03-15 Lara Daw , Stéphane Seuret
‹ Prev 1 2 3 10 Next ›