Results 31 to 40 of about 294 (153)
Choice principles and lift lemmas [PDF]
Categories and General Algebraic Structures with Applications, 2017 We show that in ZF set theory without choice, the Ultrafilter Principle (UP) is equivalent to several compactness theorems for Alexandroff discrete spaces and to Rudin's Lemma, a basic tool in topology and the theory of quasicontinuous domains. Important
Marcel Ern'e
doaj +1 more source
Topologies, posets and finite quandles
Extracta Mathematicae, 2022 An Alexandroff space is a topological space in which every intersection of open sets is open. There is one to one correspondence between Alexandroff T0 -spaces and partially ordered sets (posets).
M. Elhamdadi, H. Lahrani, T. Gona
doaj
Topologies on Zn that Are Not Homeomorphic to the n-Dimensional Khalimsky Topological Space
Mathematics, 2019 The present paper deals with two types of topologies on the set of integers, Z : a quasi-discrete topology and a topology satisfying the T 1 2 -separation axiom. Furthermore, for each n ∈ N , we develop countably many topologies on
Sang-Eon Han +2 more
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Lattice Operators and Topologies
International Journal of Mathematics and Mathematical Sciences, 2009 Working within a complete (not necessarily atomic) Boolean algebra, we use a sublattice to define a topology on that algebra. Our operators generalize complement on a lattice which in turn abstracts the set theoretic operator.
Eva Cogan
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Compact self T1-complementary spaces without isolated points
Applied General Topology, 2009 We present an example of a compact Hausdorff self T1-complementary space without isolated points. This answers Question 3.11 from [A compact Hausdorff topology that is a T1-complementof itself, Fund. Math. 175 (2002), 163–173] affirmatively.
Mikhail Tkachenko
doaj +1 more source
The Alexandroff Duplicate and its subspaces [PDF]
, 2007 We study some topological properties of the class of the Alexandroff duplicates and their subspaces. We give a characterization of metrizability and Lindel¨of properties of subspaces of the Alexandroff duplicate.
Caserta, Agata +3 more
core +1 more source
Pseudo perfectly continuous functions and closedness/compactness of their function spaces
Applied General Topology, 2013 A new class of functions called 'pseudo perfectly continuous' functions is introduced. Their place in the hierarchy of variants of continuity which already exist in the literature is highlighted.
J.K. Kohli +3 more
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Cellular structures in Topology [PDF]
, 1990 This book describes the construction and the properties of CW-complexes. These spaces are important because firstly they are the correct framework for homotopy theory, and secondly most spaces that arise in pure mathematics are of this type.
Renzo Piccinini +4 more
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On I-Alexandroff and Ig-Alexandroff ideal topological spaces
Filomat, 2011 In this paper, the notions of I -Alexandroff and Ig-Alexandroff ideal topological spaces are introduced and studied. Also, characterizations and properties of I-Alexandroff and Ig-Alexandroff ideal topological spaces are investigated.
openaire +4 more sources
Journal of Mathematics, Volume 2017, Issue 1, 2017., 2017 One of the goals of this article is to describe a setting adapted to the description of means (normalized integrals or invariant means) on an infinite product of measured spaces with infinite measure and of the concentration property on metric measured spaces, inspired from classical examples of means.
Jean-Pierre Magnot, Tepper L. Gill
wiley +1 more source