English
Related papers

Related papers: Selection properties of the split interval and the…

200 papers

In this paper we study the problems of the following kind: For a pair of topological spaces $X$ and $Y$ find sufficient conditions that under every continuous map $f : X\to Y$ a pair of sufficiently distant points is mapped to a single…

Metric Geometry · Mathematics 2025-01-22 Arseniy Akopyan , Roman Karasev , Alexey Volovikov

Let $\pi: Y\rightarrow X$ be a continuous surjection between compact Hausdorff spaces $Y$ and $X$ which is irreducible in the sense that if $F\subsetneq Y$ is closed, then $\pi(F)\neq X$. We exhibit isomorphisms between various Boolean…

General Topology · Mathematics 2025-06-11 David R. Pitts

Let $F:[0,T]\times\R^n\mapsto 2^{\R^n}$ be a continuous multifunction with compact, not necessarily convex values. In this paper, we prove that, if $F$ satisfies the following Lipschitz Selection Property: \begin{itemize} \item[{(LSP)}]…

funct-an · Mathematics 2016-08-31 Alberto Bressan , Graziano Crasta

We introduce the property of countable separation for a locally convex Hausdorff space $X$ and relate it to the existence of a metrizable coarser topology. Building on this, we demonstrate how the separability of $X$ is equivalent to the…

Functional Analysis · Mathematics 2025-10-10 Thomas Ruf

Any measure $\mu$ on a CAT(k) space M that is stratified as a finite union of manifolds and has local exponential maps near the Fr\'echet mean $\bar\mu$ yields a continuous "tangential collapse" from the tangent cone of M at $\bar\mu$ to a…

Metric Geometry · Mathematics 2023-11-17 Jonathan C. Mattingly , Ezra Miller , Do Tran

We study multiple sampling, interpolation and uniqueness for the classical Fock spaces in the case of unbounded multiplicities. We show that there are no sequences which are simultaneously sampling and interpolating when the multiplicities…

Complex Variables · Mathematics 2016-09-16 Alexander Borichev , Andreas Hartmann , Karim Kellay , Xavier Massaneda

A novel selection principle was introduced by Dorantes-Aldama and Shakhmatov: a topological space $X$ is termed {\em selectively pseudocompact} if for any sequence $(U_n:n\in {\omega})$ of pairwise disjoint non-empty open sets of $X$, one…

General Topology · Mathematics 2025-10-21 István Juhász , Lajos Soukup , Zoltán Szentmiklóssy

In this paper we continue our research of functions on the boundary of their domain and obtain some results on cluster sets of functions between topological spaces. In particular, we prove that for a metrizable topological space $X$, a…

General Topology · Mathematics 2016-02-24 O. Maslyuchenko , D. Onypa

We prove that for an indecomposable convergent or overconvergent F-isocrystal on a smooth irreducible variety over a perfect field of characteristic p, the gap between consecutive slopes at the generic point cannot exceed 1. (This may be…

Algebraic Geometry · Mathematics 2018-10-02 Vladimir Drinfeld , Kiran Kedlaya

We prove general results about separation and weak$^\#$-convergence of boundedly finite measures on separable metric spaces and Souslin spaces. More precisely, we consider an algebra of bounded real-valued, or more generally a $*$-algebra…

Probability · Mathematics 2016-09-12 Wolfgang Löhr , Thomas Rippl

We give a new characterization for mutual absolute continuity of probability measures on a filtered space. For this, we introduce a martingale limit $M$ that measures the similarity between the tails of the probability measures restricted…

Probability · Mathematics 2024-11-28 Matthias Georg Mayer

Let $(X, \mathcal{B}, \mu, T)$ be a dynamical system where $X$ is a compact metric space with Borel $\sigma$-algebra $\mathcal{B}$, and $\mu$ is a probability measure that's ergodic with respect to the homeomorphism $T : X \to X$. We study…

Dynamical Systems · Mathematics 2022-05-20 Idris Assani , Aidan Young

We discuss two ways to construct standard probability measures, called push-down measures, from internal probability measures. We show that the Wasserstein distance between an internal probability measure and its push-down measure is…

Logic · Mathematics 2020-10-07 Haosui Duanmu , William Weiss

In this work we analysed the validity of a type of Borsuk-Ulam theorem for multimaps between surfaces. We developed an algebraic technique involving braid groups to study this problem for $n$-valued maps. As a first application we described…

Algebraic Topology · Mathematics 2023-01-19 Vinicius Casteluber Laass , Carolina de Miranda e Pereiro

We prove that for every $\epsilon\in (0,1)$ there exists $C_\epsilon\in (0,\infty)$ with the following property. If $(X,d)$ is a compact metric space and $\mu$ is a Borel probability measure on $X$ then there exists a compact subset…

Metric Geometry · Mathematics 2015-06-18 Manor Mendel , Assaf Naor

Assume hat a functionally Hausdorff space $X$ is a continuous image of a \v{C}ech complete space $P$ with Lindel\"of number $l(P)<\mathfrak c$. Then the following conditions are equivalent: (i) every compact subset of $X$ is scattered, (ii)…

General Topology · Mathematics 2021-11-01 Taras Banakh , Bogdan Bokalo , Vladimir Tkachuk

It is known that Iterated Function Systems generated by orientation preserving homeomorphisms of the unit interval admit a unique invariant measure on $(0,1)$. The setup for this result is the positivity of Lyapunov exponents at both fixed…

Dynamical Systems · Mathematics 2019-06-04 Wojciech Czernous , Tomasz Szarek

Let f be a continuous map of a complete separable metric space E onto the irrationals. We show that if a complete separable metric space M contains isometric copies of every closed relatively discrete set in E, then M contains also an…

General Topology · Mathematics 2017-06-15 Elżbieta Pol , Roman Pol

The space of unitary $C_{0}$-semigroups on separable infinite dimensional Hilbert space, when viewed under the topology of uniform weak convergence on compact subsets of $\mathbb{R}_{+}$, is known to admit various interesting residual…

Functional Analysis · Mathematics 2023-02-02 Raj Dahya

Let $X$ be a compact metric space and $\mathcal M_X$ be the set of isometry classes of compact metric spaces $Y$ such that the Lipschitz distance $d_L(X,Y)$ is finite. We show that $(\mathcal M_X, d_L)$ is not separable when $X$ is a closed…

Metric Geometry · Mathematics 2015-09-15 Kohei Suzuki , Yohei Yamazaki