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Related papers: Dimension and measure in pseudofinite H-structures

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Given a subset of $X\subseteq \mathbb{R}^{n}$ we can associate with every point $x\in \mathbb{R}^{n}$ a vector space $V$ of maximal dimension with the property that for some ball centered at $x$, the subset $X$ coincides inside the ball…

Logic · Mathematics 2023-06-22 Alexis Bès , Christian Choffrut

In this paper, we completely classify $3$-dimensional complete self-expanders with constant norm $S$ of the second fundamental form and constant $f_{3}$ in Euclidean space $\mathbb R^{4}$, where $h_{ij}$ are components of the second…

Differential Geometry · Mathematics 2023-09-29 Zhi Li , Guoxin Wei

In this paper, we prove a structure theorem for the infinite union of $n$-adic doubling measures via techniques which involve far numbers. Our approach extends the results of Wu in 1998, and as a by product, we also prove a classification…

Classical Analysis and ODEs · Mathematics 2021-01-20 Theresa C. Anderson , Bingyang Hu

For countably infinite IFSs on $\mathbb R^2$ consisting of affine contractions with diagonal linear parts, we give conditions under which the affinity dimension is an upper bound for the Hausdorff dimension and a lower bound for the lower…

Dynamical Systems · Mathematics 2026-01-14 S. van Golden , C. Kalle , S. Kombrink , T. Samuel

We define and study expansion problems on countable structures in the setting of descriptive combinatorics. We consider both expansions on countable Borel equivalence relations and on countable groups, in the Borel, measure and category…

Logic · Mathematics 2025-05-13 Michael Wolman

We reconsider non-degenerate second order superintegrable systems in dimension two as geometric structures on conformal surfaces. This extends a formalism developed by the authors, initially introduced for (pseudo-)Riemannian manifolds of…

Differential Geometry · Mathematics 2024-03-15 Jonathan Kress , Konrad Schöbel , Andreas Vollmer

In this paper, we study regular sets in metric measure spaces with bounded Ricci curvature. We prove that the existence of a point in the regular set of the highest dimension implies the positivity of the measure of such regular set. Also…

Metric Geometry · Mathematics 2017-08-16 Yu Kitabeppu

Three themes of general topology: quotient spaces; absolute retracts; and inverse limits - are reapproached here in the setting of metrizable uniform spaces, with an eye to applications in geometric and algebraic topology. The results…

Geometric Topology · Mathematics 2022-11-21 Sergey A. Melikhov

Given a compact pseudo-metric space, we associate to it upper and lower dimensions, depending only on the metric. Then we construct a doubling metric for which the measure of a dillated ball is closely related to these dimensions.

Classical Analysis and ODEs · Mathematics 2007-05-23 Per Bylund , Jaume Gudayol

The purpose of this article is twofold. The first aim is to characterize $h$-extendibility of smoothly bounded pseudoconvex domains in $\mathbb C^{n+1}$ by their noncompact automorphism groups. Our second goal is to show that if the…

Complex Variables · Mathematics 2019-12-25 Ninh Van Thu , Nguyen Quang Dieu

Magnitude is an isometric invariant of metric spaces introduced by Leinster. Although magnitude is nowhere continuous on the Gromov-Hausdorff space of finite metric spaces, continuity results are possible if we restrict the ambient space.…

Metric Geometry · Mathematics 2026-03-20 Sara Kalisnik , Davorin Lesnik

The classical work of Feferman Vaught gives a powerful, constructive analysis of definability in (generalized) product structures, and certain associated enriched Boolean structures. %structures in terms of definability in the component…

Logic · Mathematics 2023-07-21 Paola D'Aquino , Angus Macintyre

Follow-up comment by the author: Theorem 2.2 in this paper is a special case of Theorems 1.1 and 4.1 in the article "Weighted thermodynamic formalism on subshifts and applications", Asian J. Math. 16 (2012), by J. Barral and D. J. Feng. In…

Dynamical Systems · Mathematics 2024-12-17 Nima Alibabaei

We prove a Structure Identity Principle for theories defined on types of $h$-level 3 by defining a general notion of saturation for a large class of structures definable in the Univalent Foundations.

Logic · Mathematics 2017-02-28 Dimitris Tsementzis

This paper concerns a stochastic construction of probabilistic coherent spaces by employing novel ingredients (i) linear exponential comonads arising properly in the measure-theory (ii) continuous orthogonality between measures and…

Logic in Computer Science · Computer Science 2023-10-10 Masahiro Hamano

We relate various concepts of fractal dimension of the limiting set C in fractal percolation to the dimensions of the set consisting of connected components larger than one point and its complement in C (the "dust"). In two dimensions, we…

Probability · Mathematics 2012-03-08 Erik Broman , Federico Camia , Matthijs Joosten , Ronald Meester

This paper addresses some questions about dimension theory for P-minimal structures. We show that, for any definable set A, the dimension of the frontier of A is strictly smaller than the dimension of A itself, and that A has a…

Logic · Mathematics 2015-09-01 Pablo Cubides-Kovacsics , Luck Darnière , Eva Leenknegt

The uniform one-dimensional fragment of first-order logic, U1, is a formalism that extends two-variable logic in a natural way to contexts with relations of all arities. We survey properties of U1 and investigate its relationship to…

Logic in Computer Science · Computer Science 2023-04-20 Antti Kuusisto

A measure is 1-rectifiable if there is a countable union of finite length curves whose complement has zero measure. We characterize 1-rectifiable Radon measures $\mu$ in $n$-dimensional Euclidean space for all $n\geq 2$ in terms of…

Metric Geometry · Mathematics 2020-07-21 Matthew Badger , Raanan Schul

A visceral structure on M is given by a definable base for a uniform topology on its universe in which all basic open sets are infinite and any infinite definable subset X of M has non-empty interior. This context includes o-minimal ordered…

Logic · Mathematics 2021-10-15 Alfred Dolich , John Goodrick