Search results for "compact groups"

showing 8 items of 8 documents

Finitary shadows of compact subgroups of $$S(\omega )$$

2020

AbstractLet LF be the lattice of all subgroups of the group $$SF(\omega )$$SF(ω) of all finitary permutations of the set of natural numbers. We consider subgroups of $$SF(\omega )$$SF(ω) of the form $$C\cap SF(\omega )$$C∩SF(ω), where C is a compact subgroup of the group of all permutations. In particular, we study their distribution among elements of LF. We measure this using natural relations of orthogonality and almost containedness. We also study complexity of the corresponding families of compact subgroups of $$S(\omega )$$S(ω).

Algebra and Number TheoryCompact groups of permutationsDistribution (number theory)Group (mathematics)010102 general mathematicsLattice (group)Almost containednessNatural number0102 computer and information sciences01 natural sciencesOmegaMeasure (mathematics)CombinatoricsOrthogonality010201 computation theory & mathematicsOrthogonality of finitary subgroupsFinitary0101 mathematicsMartin’s axiom.MathematicsAlgebra universalis
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A probabilistic meaning of certain quasinormal subgroups

2007

The role of the cyclic quasinormal subgroups has been recently described in groups both finite and infinite by S.Stonehewer and G.Zacher. This role can be better analyzed in the class of compact groups, obtaining restrictions for the probability that two randomly chosen elements commute. Mathematcs Subject Classification: 20D60, 20P05, 20D08

Discrete mathematicsSettore MAT/02 - AlgebraClass (set theory)Mutually commuting pairs commutativity degree compact groups quasinormal subgroupsProbabilistic logicSettore MAT/03 - GeometriaMeaning (existential)MathematicsInternational Journal of Algebra
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Elements with square roots in compact groups

2010

The probability that a randomly chosen element has a square root is studied in [1, 2, 8] in the finite case. Here we deal with the infinite case.

Discrete mathematicselements with square rootFunctional square rootGeneral MathematicsprobabilityFinite casecompact groupsUnit squareCombinatoricsSettore MAT/02 - AlgebraSquare rootSettore MAT/05 - Analisi MatematicaSettore MAT/03 - GeometriaElement (category theory)Square numberMathematics
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Near abelian profinite groups

2012

Abstract A compact p-group G (p prime) is called near abelian if it contains an abelian normal subgroup A such that G/A has a dense cyclic subgroup and that every closed subgroup of A is normal in G. We relate near abelian groups to a class of compact groups, which are rich in permuting subgroups. A compact group is called quasihamiltonian (or modular) if every pair of compact subgroups commutes setwise. We show that for p ≠ 2 a compact p-group G is near abelian if and only if it is quasihamiltonian. The case p = 2 is discussed separately.

Pure mathematicsProfinite groupApplied MathematicsGeneral Mathematicstopologically quasihamiltonian groupProjective covermodular groupcompact groupsSettore MAT/03 - GeometriaAbelian groupMathematicspro-$p$-group
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Locally compact groups which are just not compact

2010

A Just-Non-Compact group, or briefly a JNC group, is a Hausdorff topological group which is not a compact group but all of whose proper Hausdorff quotients are compact groups. Intuitively, it is clear that these groups are rich in compact quotients. Locally compact JNC groups are largely described in the present paper.

Pure mathematicsSettore MAT/02 - AlgebraSettore MAT/05 - Analisi MatematicaGeneral MathematicsJust-Non-Compact groups Lie groups compact groupsLie groupLocally compact spaceSettore MAT/03 - GeometriaMathematics
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On compact Just-Non-Lie groups

2007

A compact group is called a compact Just-Non-Lie group or a compact JNL group if it is not a Lie group but all of its proper Hausdorff quotient groups are Lie groups. We show that a compact JNL group is profinite and a compact nilpotent JNL group is the additive group of p -adic integers for some prime. Examples show that this fails for compact pronilpotent and solvable groups.

Settore MAT/02 - AlgebraSettore MAT/03 - Geometriacompact Just-Non-Lie groups centerfree compact groups
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Probability of mutually commuting n-tuples in some classes of compact groups

2008

In finite groups the probability that two randomly chosen elements commute or randomly ordered n−tuples of elements mutually commute have recently attracted interest by many authors. There are some classical results estimating the bounds for this kind of probability so that the knowledge of the whole structure of the group can be more accurate. The same problematic has been recently extended to certain classes of infinite compact groups in [2], obtaining restrictions on the group of the inner automorphisms. Here such restrictions are improved for a wider class of infinite compact groups.

Settore MAT/02 - AlgebraSettore MAT/05 - Analisi MatematicaSettore MAT/03 - GeometriaMutually commuting n-tuples commutativity degree compact groups topological groups
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A note on relative isoclinism classes of compact groups

2009

Settore MAT/02 - AlgebraSettore MAT/05 - Analisi MatematicaSettore MAT/03 - Geometriacompact groups Haar measure $p$-groups commutativity degree
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