Results 41 to 50 of about 6,858,530 (350)
Universal countable Borel quasi-orders [PDF]
, 2013 In recent years, much work in descriptive set theory has been focused on the Borel complexity of naturally occurring classification problems, in particular, the study of countable Borel equivalence relations and their structure under the quasi-order of ...
Williams, Jay
core +4 more sources
Lebesgue Measurability of Separately Continuous Functions and Separability
International Journal of Mathematics and Mathematical Sciences, 2007 A connection between the separability and the countable chain condition of spaces with L-property (a topological space X has L-property if for every topological space Y, separately continuous function f:X×Y→ℝ and open set I⊆ℝ, the set f−1(I) is an Fσ-set)
V. V. Mykhaylyuk
doaj +1 more source
Equidistribution of Elements of Norm 1 in Cyclic Extensions [PDF]
, 2014 Upon quotienting by units, the elements of norm 1 in a number field $K$ form a countable subset of a torus of dimension $r_1 + r_2 - 1$ where $r_1$ and $r_2$ are the numbers of real and pairs of complex embeddings.
Petersen, Kathleen L. +1 more
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Classification of dendrites with a countable set of end points
, 2012 We prove that for each countable ordinal α in the family of dendrites X with a countable set of end points such that the α -derivative of the set of end points of X is empty there is no universal element.
Sophia Zafiridou
semanticscholar +1 more source
Compact-calibres of regular and monotonically normal spaces
International Journal of Mathematics and Mathematical Sciences, 2002 A topological space has calibre ω1 (resp., calibre (ω1,ω)) if every point-countable (resp., point-finite) collection of nonempty open sets is countable.
David W. Mcintyre
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Neutrosophic µ-Topological spaces [PDF]
Neutrosophic Sets and Systems, 2020 In this paper, the concept of neutrosophic µ−topological spaces is introduced. We define and study the properties of neutrosophic µ−open sets, µ−closed sets, µ−interior and µ−closure.
Murad Arar, Saeid Jafari
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Pcf theory and cardinal invariants of the reals [PDF]
, 2004 The additivity spectrum ADD(I) of an ideal I is the set of all regular cardinals kappa such that there is an increasing chain {A_alpha ...
Burke, Masaru Kada, Maxim R. Burke
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On Hausdorff compactifications of non-locally compact spaces
International Journal of Mathematics and Mathematical Sciences, 1979 Let X be a completely regular, Hausdorff space and let R be the set of points in X which do not possess compact neighborhoods. Assume R is compact. If X has a compactification with a countable remainder, then so does the quotient X/R, and a countable ...
James Hatzenbuhler, Don A. Mattson
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Structural aspects of tilings [PDF]
, 2008 In this paper, we study the structure of the set of tilings produced by any given tile-set. For better understanding this structure, we address the set of finite patterns that each tiling contains.
Ballier, Alexis +2 more
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Journal of Inequalities and Applications, 2010 We introduce two iterative sequence for finding a common element of the set of solutions of an equilibrium problem and the set of fixed points of a countable family of strict pseudocontractions in Hilbert Space.
Shujun Cui, Xilin Shen, Rudong Chen
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