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Related papers: Equivalent Conditions for Digital Covering Maps

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SE Han's paper [11] discusses several variants of digital covering maps. We show several equivalences among these variants and discuss shortcomings in Han's paper.

Geometric Topology · Mathematics 2023-08-15 Laurence Boxer

We investigate the properties of digital homotopy in the context of digital pictures $(X,\kappa,\bar \kappa)$, where $X\subsetneq \Z^n$ is a finite set, $\kappa$ is an adjacency relation on $X$, and $\bar \kappa$ is an adjacency relation on…

Algebraic Topology · Mathematics 2025-09-18 Dae-Woong Lee , P. Christopher Staecker

In this paper, by reviewing the concept of subcovering and semicovering maps, we extend the notion of subcovering map to subsemicovering map. We present some necessary or sufficient conditions for a local homeomorphism to be a…

Algebraic Topology · Mathematics 2016-07-04 Majid Kowkabi , Behrooz Mashayekhy , Hamid Torabi

It is well-known that a homomorphism p between topological groups K, G is a covering homomorphism if and only if p is an open epimorphism with discrete kernel. In this paper we generalize this fact, in precisely, we show that for a…

Algebraic Topology · Mathematics 2018-08-28 Hamid Torabi , Mehdi Abdullahi Rashid , Majid Kowkabi

We study a natural generalization of covering projections defined in terms of unique lifting properties. A map $p:E\to X$ has the "continuous path-covering property" if all paths in $X$ lift uniquely and continuously (rel. basepoint) with…

Algebraic Topology · Mathematics 2025-01-27 Jeremy Brazas , Atish Mitra

In this paper, we establish a new criterion for covering maps between real algebraic varieties. Specifically, we prove that a quasi-finite, flat morphism with locally constant geometric fibers between varieties over a real closed field…

Algebraic Geometry · Mathematics 2026-03-10 Rizeng Chen

The $\lambda$-perfect maps, a generalization of perfect maps (continuous closed maps with compact fibers) are presented. Using $P_\lambda$-spaces and the concept of $\lambda$-compactness some results regarding $\lambda$-perfect maps will be…

General Topology · Mathematics 2016-10-25 M. Namdari , M. A. Siavoshi

The notions of a local $(k_0,k_1)$-isomorphism and a weakly local $(k_0,k_1)$-isomorphism play crucial roles in developing a digital $(k_0,k_1)$-covering space and a pseudo-$(k_0,k_1)$-covering space, respectively. In relation to the study…

General Topology · Mathematics 2023-09-06 Sang-Eon Han

The aim of this paper is to generalize some of the properties and results regarding both the coincidence point set and the common fixed point set of any two digitally continuous maps to the case of several (more than two) digitally…

General Topology · Mathematics 2019-11-19 Muhammad Sirajo Abdullahi , Poom Kumam , Isah Abor Garba

In this study, we improve the topological complexity computations on digital images with introducing the digital topological complexity computations of a surjective and digitally continuous map between digital images. We also reveal…

Algebraic Topology · Mathematics 2021-03-02 Melih Is , Ismet Karaca

In this paper, by reviewing the concept of semicovering maps, we present some conditions under which a local homeomorphism becomes a semicovering map. We also obtain some conditions under which a local homeomorphism is a covering map.

Algebraic Topology · Mathematics 2016-07-26 Majid Kowkabi , Behrooz Mashayekhy , Hamid Torabi

We develop an abstract model for the dynamics of an exponential map $z\mapsto \exp(z)+\kappa$ on its set of escaping points and, as an analog of Boettcher's theorem for polynomials, show that every exponential map is conjugate, on a…

Dynamical Systems · Mathematics 2007-10-28 Lasse Rempe

A cardinal kappa is countably closed if mu^omega < kappa whenever mu < kappa. Assume that there is no inner model with a Woodin cardinal and that every set has a sharp. Let K be the core model. Assume that kappa is a countably closed…

Logic · Mathematics 2016-09-07 William J. Mitchell , Ernest Schimmerling , John R. Steel

We develop a combinatorial framework to study certain polyhedral maps which are higher-dimensional analogues of tropical covers between metric graphs. Under a mild combinatorial assumption, we show that a map satisfies the so-called…

Combinatorics · Mathematics 2023-05-08 Alejandro Vargas

Local properties of the fundamental group of a path-connected topological space can pose obstructions to the applicability of covering space theory. A generalized covering map is a generalization of the classical notion of covering map…

Algebraic Topology · Mathematics 2020-04-14 Jeremy Brazas , Hanspeter Fischer

We prove that $i)$ if $\mathcal{A}$ is $\lambda $-accessible and it is axiomatizable in (finitary) coherent logic then $\lambda $-pure maps are strict monomorphisms and $ii)$ if there is a proper class of strongly compact cardinals and…

Category Theory · Mathematics 2025-06-05 Kristóf Kanalas

We add to our knowledge of the approximate fixed point property (AFPP) in digital topology. We show that a digital image that is a tree has the AFPP. Given two digital images (X, \kappa) and (Y, \lambda) that have the approximate fixed…

Geometric Topology · Mathematics 2020-04-08 Laurence Boxer

Let $M$ be a $2$-space form. Let $P$ be a convex polygon in $M$. For these polygons, we define (and justify) a curvature $\kappa_i$ at each vertex $A_i$ of the polygon and and prove the following Blaschke's type theorem: If $P$ is a convex…

Differential Geometry · Mathematics 2023-05-15 Alexander Borisenko , Vicente Miquel

A map $p:E\to X$ has the \emph{unique path lifting} property if every path in $X$, after a choice of an initial point, lifts uniquely to a path in $E$. We prove that if a group $G$ acts on an $\mathbb R$-tree $T$ such that the quotient map…

Algebraic Topology · Mathematics 2026-05-27 Jeremy Brazas , Gregory R. Conner , Paul Fabel , Curtis Kent

Dynamic maps that allow continuous map rotations, e.g., on mobile devices, encounter new issues unseen in static map labeling before. We study the following dynamic map labeling problem: The input is a static, labeled map, i.e., a set P of…

Computational Geometry · Computer Science 2011-05-02 Andreas Gemsa , Martin Nöllenburg , Ignaz Rutter
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