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We prove that continuous reducibility is a well-quasi-order on the class of continuous functions between separable metrizable spaces with analytic zero-dimensional domain. To achieve this, we define scattered functions, which generalize…

Logic · Mathematics 2024-10-18 Raphaël Carroy , Yann Pequignot

Let $S$ denote the graded polynomial ring $\C[x_1,...,x_m]$. We interpret a chain complex of free $S$-modules having finite length homology modules as an $S^1$-equivariant map $\C^m\sm\{0\} \to X$, where $X$ is a moduli space of exact…

Algebraic Topology · Mathematics 2009-11-17 T. B. Williams

In this paper the concept of a partial cone metric space is investigated, some continuity type theorems, and fixed point theorems of contractive mappings in this generalized setting are proved as well as some theorems related to topological…

General Topology · Mathematics 2012-09-20 Ayse Sonmez

We study proportions of consecutive occurrences of permutations of a given size. Specifically, the limit of such proportions on large permutations forms a region, called \emph{feasible region}. We show that this feasible region is a…

Combinatorics · Mathematics 2021-01-22 Jacopo Borga , Raul Penaguiao

Generalizations of the theorems of Eberlein and Grothendieck on the precompactness of subsets of function spaces are considered: if $X$ is a countably compact space and $C_p(X)$ is a space of continuous functions in the pointwise topology…

General Topology · Mathematics 2024-11-06 E. A. Reznichenko

We construct a complete locally convex topological vector space $X$ of countable algebraic dimension and a continuous linear operator $T:X\to X$ such that $T$ has no non-trivial closed invariant subspaces.

Functional Analysis · Mathematics 2010-09-15 Stanislav Shkarin

We develop persistent homology in the setting of filtrations of (Cech) closure spaces. Examples of filtrations of closure spaces include metric spaces, weighted graphs, weighted directed graphs, and filtrations of topological spaces. We use…

Algebraic Topology · Mathematics 2025-02-19 Peter Bubenik , Nikola Milićević

Cohomological ideas have recently been injected into persistent homology and have for example been used for accelerating the calculation of persistence diagrams by the software Ripser. The cup product operation which is available at…

Algebraic Topology · Mathematics 2022-12-20 Marco Contessoto , Facundo Mémoli , Anastasios Stefanou , Ling Zhou

We investigate the Baire classification of mappings $f:X\times Y\to Z$, where $X$ belongs to a wide class of spaces, which includes all metrizable spaces, $Y$ is a topological space, $Z$ is an equiconnected space, which are continuous in…

General Topology · Mathematics 2014-07-23 Olena Karlova , Volodymyr Maslyuchenko , Volodymyr Mykhaylyuk

We show that every continuous map from one translationally finite tiling space to another can be approximated by a local map. If two local maps are homotopic, then the homotopy can be chosen so that every interpolating map is also local.

Dynamical Systems · Mathematics 2018-07-10 Betseygail Rand , Lorenzo Sadun

This paper is a sequel to [1] and considers definability in differential-henselian monotone fields with c-map and angular component map. We prove an Equivalence Theorem among whose consequences are a relative quantifier reduction and an NIP…

Logic · Mathematics 2018-06-11 Tigran Hakobyan

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

In this paper, we introduce the notion of partially ordered {\epsilon}-chainable metric spaces and we derive new coupled fixed point theorems for uniformly locally contractive mappings on such spaces.

General Topology · Mathematics 2010-05-19 Bessem Samet , Habib Yazidi

A Tychonoff space $X$ is called ({\em sequentially}) {\em Ascoli} if every compact subset (resp. convergent sequence) of $C_k(X)$ is equicontinuous, where $C_k(X)$ denotes the space of all real-valued continuous functions on $X$ endowed…

General Topology · Mathematics 2020-04-29 Saak Gabriyelyan

Motivated by a recent result of Sakai, we define a new selection operator for covers of topological spaces, inducing new selection hypotheses. We initiate a systematic study of the new hypotheses. Some intriguing problems remain open.

General Topology · Mathematics 2010-11-02 Boaz Tsaban

In this paper, the concept of quasi-finitely separating map and quasiapproximate identity are introduced. Based on these concepts, QFS-spaces and quasicontinuous maps are defined. Properties and characterizations of QFS-spaces are explored.…

General Topology · Mathematics 2022-12-14 Wu Wang

In this paper we consider a problem of searching a space of predictive models for a given training data set. We propose an iterative procedure for deriving a sequence of improving models and a corresponding sequence of sets of non-linear…

Machine Learning · Computer Science 2014-02-18 Michael Tetelman

The aim of this paper is to present a method for computation of persistent homology that performs well at large filtration values. To this end we introduce the concept of filtered covers. We show that the persistent homology of a bounded…

Algebraic Topology · Mathematics 2018-05-29 Nello Blaser , Morten Brun

We mainly introduce some weak versions of the $M_{1}$-spaces, and study some properties about these spaces. The mainly results are that: (1) If $X$ is a compact scattered space and $i(X)\leq 3$, then $X$ is an $s$-$m_{1}$-space; (2) If $X$…

General Topology · Mathematics 2013-02-19 Fucai Lin , Shou Lin

We develop a continued fraction algorithm in finite extensions of $\Q_p$ generalising certain algorithms in $\Q_p$, and prove the finiteness property for certain small degree extensions. We also discuss the metrical properties of the…

Number Theory · Mathematics 2024-07-08 Manoj Choudhuri , Prashant J. Makadiya