Results 81 to 90 of about 1,820 (180)
Selective ultrafilters and homogeneity
Annals of Pure and Applied Logic, 1988 This paper consists, roughly speaking, of three parts: in the first part the author refines older results on the existence of homogeneous sets for partitions of \([\omega]^{\omega}\). An interesting byproduct of these investigations is the result that: if every ccc forcing adds either a Cohen or a random real, then there are no P-points.
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A Machine Proof of the Filter-Method Construction for Real Numbers
MathematicsThis paper presents a machine verification of a real number theory where real numbers are constructed using concepts related to filters. The theory encompasses a special filter, namely the non-principal arithmetical ultrafilter whose existence can be ...
Guowei Dou, Wensheng Yu
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Selectively Pseudocompact Groups without Infinite Separable Pseudocompact Subsets
Axioms, 2018 We give a “naive” (i.e., using no additional set-theoretic assumptions beyond ZFC, the Zermelo-Fraenkel axioms of set theory augmented by the Axiom of Choice) example of a Boolean topological group G without infinite separable pseudocompact subsets ...
Dmitri Shakhmatov, Víctor Hugo Yañez
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A categorical construction of ultrafilters
Rocky Mountain Journal of Mathematics, 2010 5 ...
Litt, Daniel +2 more
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Ideals in B1(X) and residue class rings of B1(X) modulo an ideal
Applied General Topology, 2019 This paper explores the duality between ideals of the ring B1(X) of all real valued Baire one functions on a topological space X and typical families of zero sets, called ZB-filters, on X.
A. Deb Ray, Atanu Mondal
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Ultrafilter in Digraph: Directed Tangle and Directed Ultrafilter
Journal of Advances in Mathematics and Computer ScienceTangle is a concept in graph theory that has a dual relationship with tree-width which is well-known graph width parameter. Ultrafilter is a fundamental notion in mathematics. In this concise paper, we will reconsider the relationship between Tangle and Ultrafilter in digraph.
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Approximations of Theories of Unars
Қарағанды университетінің хабаршысы. Математика сериясыLo´s’s theorem states that a first-order formula holds in an ultraproduct of structures if and only if it holds in “almost all” factors, where “almost all” is understood in terms of a given ultrafilter.
N.D. Markhabatov
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Criterion for a formula-definable quasivariety
Қарағанды университетінің хабаршысы. Математика сериясыIn this paper, we study classes of models of a first-order language L with a countable signature σ. For a model A, let Th(A) denote the set of all sentences of L that are true in A, called the elementary type of A.
M.I. Bekenov +3 more
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A Boolean model of ultrafilters
Annals of Pure and Applied Logic, 1999 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Collagen IV of basement membranes: II. Emergence of collagen IVα345 enabled the assembly of a compact GBM as an ultrafilter in mammalian kidneys. [PDF]
J Biol Chem, 2023 Pokidysheva EN +14 more
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