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Related papers: Extremal k-pseudocompact abelian groups

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We show that every compact connected group is the limit of a continuous inverse sequence, in the category of compact groups, where each successor bonding map is either an epimorphism with finite kernel or the projection from a product by a…

General Topology · Mathematics 2012-10-23 Wiesław Kubiś , Sławomir Turek

The generalised Fitting subgroup of a finite group is the group generated by all subnormal subgroups that are either nilpotent or quasisimple. The importance of this subgroup in finite group theory stems from the fact that it always…

Group Theory · Mathematics 2009-04-03 Colin Reid

The authors investigate the structure of quasi-o-minimal groups. Among other results, they show that quasi-o-minimal groups are abelian, that quasi-o-minimal densely ordered archimedian groups are divisible, and that every divisible…

Rings and Algebras · Mathematics 2008-02-03 Oleg Belegradek , Ya'acov Peterzil , Frank Wagner

In this article, we show that there exist discrete isometry groups of the $2$- and $3$-dimensional complex hyperbolic spaces with critical exponents arbitrarily close to but strictly smaller than the maximum possible value. This result…

Geometric Topology · Mathematics 2023-10-10 Subhadip Dey , Beibei Liu

We give bounds on Kazhdan constants of abelian extensions of (finite) groups. As a corollary, we improved known results of Kazhdan constants for some meta-abelian groups and for the relatively free group in the variety of $p$-groups of…

Group Theory · Mathematics 2010-07-27 Uzy Hadad

The discrete cocompact subgroups of the five-dimensional connected, simply connected nilpotent Lie groups are determined up to isomorphism. Moreover, we prove if $G=N\times A$ is a connected, simply connected, nilpotent Lie group with an…

Group Theory · Mathematics 2009-02-18 Amira Ghorbel , Hatem Hamrouni

In this paper, we describe the relationship between the quasi-component q(G) of a (perfectly) minimal pseudocompact abelian group G and the quasi-component q(\widetilde G) of its completion. Specifically, we characterize the pairs (C,A) of…

General Topology · Mathematics 2012-03-19 D. Dikranjan , Gábor Lukács

Let a compact group G act on real or complex C*-algebras A and B, with A separable and B sigma-unital. We express the G-equivariant Kasparov groups KK_n(A,B) by algebraic K-groups of a certain additive category.

K-Theory and Homology · Mathematics 2007-05-23 Tamaz Kandelaki

Necessary and sufficient conditions for finite commutative semihypergroups to be built from abelian groups of the same order are established.

Representation Theory · Mathematics 2017-03-08 Stan Onypchuk

We provide characterizations of Lie groups as compact-like groups in which all closed zero-dimensional metric (compact) subgroups are discrete. The "compact-like" properties we consider include (local) compactness, (local)…

General Topology · Mathematics 2018-03-05 Dikran Dikranjan , Dmitri Shakhmatov

We study generic properties of topological groups in the sense of Baire category. First we investigate countably infinite (discrete) groups. We extend a classical result of B. H. Neumann, H. Simmons and A. Macintyre on algebraically closed…

We study ergodic invariant random subgroups that give full measure to the subset of compact subgroups. We show that in real Lie groups, compactly generated $p$-adic Lie groups, locally compact hyperbolic groups and infinitely ended groups…

Group Theory · Mathematics 2026-03-18 Tal Cohen , Helge Glöckner , Gil Goffer , Waltraud Lederle

Let K be a Cantor set embedded in the real line R. Following Funar and Neretin, we define the diffeomorphism group of K as the group of homeomorphisms of K which locally look like a diffeomorphism between two intervals of R.…

Dynamical Systems · Mathematics 2023-02-16 Dominique Malicet , Emmanuel Militon

We give an accessible and modern description of the automorphisms of a finite abelian group $G$. Included is an explicit formula for the cardinality of $Aut(G)$.

Group Theory · Mathematics 2007-05-23 Christopher J. Hillar , Darren Rhea

In this paper we generalize Kingman's sub-additive ergodic theorem to a large class of infinite countable discrete amenable group actions.

Dynamical Systems · Mathematics 2014-12-23 Anthony H. Dooley , Valentyn Ya. Golodets , Guohua Zhang

Recently, Paolini and Shelah have constructed absolutely Hopfian torsion-free abelian groups of any given size. In contrast, we show that this is not necessarily the case for absolutely co-Hopfian groups. We use the infinitary logic to show…

Logic · Mathematics 2024-11-28 Mohsen Asgharzadeh , Mohammad Golshani , Saharon Shelah

We study the structure of invariant measures for continuous automorphisms of compact metrizable abelian groups satisfying the descending chain condition. We show that the finitely supported invariant measures are weak-* dense in the space…

Dynamical Systems · Mathematics 2025-07-21 Rotem Yaari

Farre, Pozzetti and Viaggi proved that any (d-k)-hyperconvex subgroup of PSL(d,C) is virtually isomorphic to a convex cocompact Kleinian group and that its k-th simple root critical exponent is at most 2. We show that a (d-k)-hyperconvex…

Differential Geometry · Mathematics 2025-12-25 Richard Canary , Tengren Zhang , Andrew Zimmer

In this paper, we deal with locally graded groups whose subgroups are either subnormal or soluble of bounded derived length, say d. In particular, we prove that every locally (soluble-by-finite) group with this property is either soluble or…

Group Theory · Mathematics 2015-04-02 Kivanc Ersoy , Antonio Tortora , Maria Tota

We list all finite abelian groups which act effectively on smooth cubic fourfolds.

Algebraic Geometry · Mathematics 2013-09-03 Evgeny Mayanskiy