Results 41 to 50 of about 383 (157)
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
Some Topological Notations via Maki’s Λ‐Sets
Complexity, Volume 2020, Issue 1, 2020., 2020 Our purpose is to present the notions of a β‐Λ‐set and a β‐V‐sets in topological space. We discuss the basic properties of β‐Λ‐sets and β‐V‐sets. Also, the achievement of the topology defined by these families of sets is obtained. Finally, these results are applied to the case of (X, τ) which is the digital n‐space (Zn, Kn) (cf. Section 4).
A. A. Azzam +2 more
wiley +1 more source
Disconnection in the Alexandroff duplicate [PDF]
, 2021 [EN] It was demonstrated in [2] that the Alexandroff duplicate of the Čech-Stone compactification of the naturals is not extremally disconnected. The question was raised as to whether the Alexandroff duplicate of a non-discrete extremally disconnected ...
Knox, Michelle L. +5 more
core +1 more source
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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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
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, 2021 ilustraciones, gráficasEn este trabajo se realiza un estudio de las propiedades que tienen los espacios funcionales de Alexandroff y se presenta una forma de caracterizarlos a través de su preorden de especialización.
Mesa Bueno, Julian David
core
The compactificability classes: The behavior at infinity
International Journal of Mathematics and Mathematical Sciences, 2006 We study the behavior of certain spaces and their compactificability classes at infinity. Among other results we show that every noncompact, locally compact, second countable Hausdorff space X such that each neighborhood of infinity (in the Alexandroff ...
Martin Maria Kovár
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Cofinitely and co-countably projective spaces
Applied General Topology, 2002 We show that X is cofinitely projective if and only if it is a finite union of Alexandroff compactatifications of discrete spaces. We also prove that X is co-countably projective if and only if X admits no disjoint infinite family of uncountable cozero ...
Pablo Mendoza Iturralde +1 more
doaj +1 more source
Global Policy, Volume 17, Issue 2, Page 178-188, May 2026.ABSTRACT The growing significance of informal intergovernmental organisations (IIGOs) in global politics necessitates a re‐evaluation of leadership dynamics. We develop a theory framework that enables us to explain why countries take on leadership roles in IIGOs, with a specific focus on climate politics.
Christin Heinz‐Fischer +1 more
wiley +1 more source
Structural Properties of Soft Biposets With Generalizations of Submaximal and Door Posets
Journal of Mathematics, Volume 2026, Issue 1, 2026.Soft biposet presented in this work is a new generalization of the notion of poset to soft set theory. This generalization not only equips the universal set with a partial order but also introduces another partial order on the set of parameters. Moreover, we extend the notions of submaximal and door posets to soft biposets.
Abdelwaheb Mhemdi, Smritijit Sen
wiley +1 more source