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Related papers: A note on small sets of reals

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In this paper we present a simple approach to big Ramsey combinatorics of the Cantor set $2^\omega$. Using Infinite Dual Ramsey Theorem of Carlson and Simpson, we show that $2^\omega$, viewed as a topological space, has finite big Ramsey…

Logic · Mathematics 2026-02-24 Dragan Mašulović

It was shown by Antunovi\'{c}, Burdzy, Peres, and Ruscher that a Cantor function added to one-dimensional Brownian motion has zeros in the middle $\alpha$-Cantor set, $\alpha \in (0,1)$, with positive probability if and only if $\alpha \neq…

Probability · Mathematics 2012-07-26 Julia Ruscher

Every element $u$ of $[0,1]$ can be written in the form $u=x^2y$, where $x,y$ are elements of the Cantor set $C$. In particular, every real number between zero and one is the product of three elements of the Cantor set. On the other hand…

Metric Geometry · Mathematics 2017-11-27 Jayadev S. Athreya , Bruce Reznick , Jeremy T. Tyson

A Cantor set is a non-empty, compact set that has neither interior nor isolated points. In this paper a Cantor set $K\subseteq \mathbb{R}$ is constructed such that every set definable in $(\mathbb{R},<,+,\cdot,K)$ is Borel. In addition, we…

Logic · Mathematics 2016-05-04 Philipp Hieronymi

Given a sequence of subsets A_n of {0,...,n-1}, the Furstenberg correspondence principle provides a shift-invariant measure on Cantor space that encodes combinatorial information about infinitely many of the A_n's. Here it is shown that…

Combinatorics · Mathematics 2012-02-03 Jeremy Avigad

We study the cardinal invariants of measure and category after adding one random real. In particular, we show that the number of measure zero subsets of the plane which are necessary to cover graphs of all continuous functions maybe large…

Logic · Mathematics 2016-09-06 Tomek Bartoszyński , Andrzej Rosłanowski , Saharon Shelah

Given any dimension function $h$, we construct a perfect set $E \subseteq \mathbb{R}$ of zero $h$-Hausdorff measure, that contains any finite polynomial pattern. This is achieved as a special case of a more general construction in which we…

Classical Analysis and ODEs · Mathematics 2020-02-19 Ursula Molter , Alexia Yavicoli

In 1994, J.Cobb constructed a tame Cantor set in $\mathbb R^3$ each of whose projections into $2$-planes is one-dimensional. We show that an Antoine's necklace can serve as an example of a Cantor set all of whose projections are…

Geometric Topology · Mathematics 2022-12-07 Olga Frolkina

In this paper we discuss several variations and generalizations of the Cantor set and study some of their properties. Also for each of those generalizations a Cantor-like function can be constructed from the set. We will discuss briefly the…

Classical Analysis and ODEs · Mathematics 2014-03-27 Robert DiMartino , Wilfredo Urbina

Below, by space we mean a separable metrizable zero-dimensional space. It is studied when the space can be embedded in a Cantor set while maintaining the algebraic structure. Main results of the work: every space is an open retract of a…

General Topology · Mathematics 2023-06-13 Evgenii Reznichenko

We investigate variants of the Erd\H{o}s similarity problem for Cantor sets. We prove that under a mild Hausdorff or packing logarithmic dimension assumption, Cantor sets are not full measure universal, significantly improving the known…

Classical Analysis and ODEs · Mathematics 2025-12-22 Pablo Shmerkin , Alexia Yavicoli

We provide new techniques to construct sets of reals without perfect subsets and with the Hurewicz or Menger covering properties. In particular, we show that if the Continuum Hypothesis holds, then there are such sets which can be mapped…

General Topology · Mathematics 2026-03-02 Piotr Szewczak , Tomasz Weiss , Lyubomyr Zdomskyy

We study the randomness properties of reals with respect to arbitrary probability measures on Cantor space. We show that every non-computable real is non-trivially random with respect to some measure. The probability measures constructed in…

Logic · Mathematics 2013-05-16 Jan Reimann , Theodore A. Slaman

An important theorem of geometric measure theory (first proved by Besicovitch and Davies for Euclidean space) says that every analytic set of non-zero $s$-dimensional Hausdorff measure $\mathcal H^s$ contains a closed subset of non-zero…

Logic · Mathematics 2014-08-12 Bjørn Kjos-Hanssen , Jan Reimann

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 lay the combinatorial foundations for [ShSt:340] by setting up and proving the essential properties of the coding apparatus for singular cardinals. We also prove another result concerning the coding apparatus for inaccessible cardinals.

Logic · Mathematics 2016-09-06 Saharon Shelah , Lee Stanley

We consider (not self-similar) Cantor sets defined by a sequence of piecewise linear functions. We prove that the dimension of the harmonic measure on such a set is strictly smaller than its Hausdorff dimension. Some Hausdorff measure…

Classical Analysis and ODEs · Mathematics 2013-03-19 Athanasios Batakis , Anna Zdunik

We prove a Khintchine type theorem for approximation of elements in the Cantor set, as a subset of the formal Laurent series over $\mathbb{F}_3$, by rational functions of a specific type. Furthermore we construct elements in the Cantor set…

Number Theory · Mathematics 2014-09-02 Steffen Højris Pedersen

We prove that in a Euclidean space of dimension at least two, there exists a compact set of Lebesgue measure zero such that any real-valued Lipschitz function defined on the space is differentiable at some point in the set. Such a set is…

Functional Analysis · Mathematics 2011-05-17 Michael Doré , Olga Maleva

Let L be the zero set of a nonconstant monic polynomial with complex coefficients. In the context of constructive mathematics without countable choice, it may not be possible to construct an element of L. In this paper we introduce a notion…

Logic · Mathematics 2015-10-06 Robert Lubarsky , Fred Richman