منابع مشابه
Characterized Subgroups of Topological Abelian Groups
A subgroup H of a topological abelian group X is said to be characterized by a sequence v = (vn) of characters of X if H = {x ∈ X : vn(x) → 0 in T}. We study the basic properties of characterized subgroups in the general setting, extending results known in the compact case. For a better description, we isolate various types of characterized subgroups. Moreover, we introduce the relevant class o...
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Let X be a compact metrizable abelian group and u = {un} be a sequence in its dual X. Set su(X) = {x : (un, x) → 1} and T H 0 = {(zn) ∈ T ∞ : zn → 1}. Let G be a subgroup of X. We prove that G = su(X) for some u iff it can be represented as some dually closed subgroup Gu of ClXG × T H 0 . In particular, su(X) is polishable. Let u = {un} be a T -sequence. Denote by (X̂,u) the group X ∧ equipped w...
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A sequence {un}n∈ω in abstract additively-written Abelian group G is called a T -sequence if there is a Hausdorff group topology on G relative to which limn un = 0. We say that a subgroupH of an infinite compact Abelian groupX is T -characterized if there is a T -sequence u = {un} in the dual group of X , such that H = {x ∈ X : (un, x) → 1}. We show that a closed subgroupH ofX is T -characteriz...
متن کاملOnmodular inequalities of interval-valued fuzzy soft sets characterized by soft J-inclusions
*Correspondence: [email protected] 1Department of Applied Mathematics, School of Science, Xi’an University of Posts and Telecommunications, Xi’an, 710121, China Full list of author information is available at the end of the article Abstract This study aims to explore modular inequalities of interval-valued fuzzy soft sets characterized by Jun’s soft J-inclusions. Using soft product operations...
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We define a notion of depth for an inclusion of multimatrix algebras B ⊆ A based on a comparison of powers of the inductionrestriction table M (and its transpose matrix). The depth of the semisimple subalgebra B in the semisimple algebra A is the least positive integer n ≥ 2 for which M ≤ qM for some q ∈ Z+. We prove that a depth two subalgebra is a normal subalgebra, and conversely. As a corol...
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 2017
ISSN: 0166-8641
DOI: 10.1016/j.topol.2017.02.004