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Related papers: A sofic group away from amenable groups

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We classify the factorizations of finite classical groups with nonsolvable factors, completing the classification of factorizations of finite almost simple groups.

Group Theory · Mathematics 2024-07-26 Cai Heng Li , Lei Wang , Binzhou Xia

We generalize the notion of self-similar groups of infinite tree automorphisms to allow for groups which are defined on a tree but do not act faithfully on it. The elements of such a group correspond to labeled trees which may be recognized…

Group Theory · Mathematics 2019-07-15 Andrew Penland , Zoran Šunić

In this article we prove that an "isometric multiple HNN-extension" of a group satisfying the falsification by fellow traveler property is almost convex. As a corollary, Wise's example of a CAT(0) non-Hopfian group is Almost convex.

Group Theory · Mathematics 2012-05-16 Murray J Elder

We consider a few types of bounded homomorphisms on a topological group. These classes of bounded homomorphisms are, in a sense, weaker than the class of continuous homomorphisms. We show that with appropriate topologies each class of these…

General Topology · Mathematics 2015-08-25 Ljubisa D. R. Kocinac , Omid Zabeti

We prove that there exists a group which is not finitely generated, but admits a minimal sofic shift. This answers a question of Doucha, Melleray and Tsankov. The group is of the form $(F_4 \times F_2) \rtimes F_{\infty}$. The construction…

Dynamical Systems · Mathematics 2025-07-10 Ville Salo

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

A group is $\textit{finitely axiomatizable}$ (FA) in a class $\mathcal{C}$ if it can be determined up to isomorphism within $\mathcal{C}$ by a sentence in the first-order language of group theory. We show that profinite groups of various…

Group Theory · Mathematics 2021-05-25 Andre Nies , Dan Segal , Katrin Tent

In this article we introduce and study a class of finite groups for which the orders of normal subgroups satisfy a certain inequality. It is closely connected to some well-known arithmetic classes of natural numbers.

Group Theory · Mathematics 2018-05-31 Marius Tărnăuceanu

In this paper we extend the approach of M. Cavaleri to effective amenability to the class of computably enumerable groups, i.e. in particular we do not assume that groups are finitely generated. In the case of computable groups we also…

Group Theory · Mathematics 2022-05-16 Karol Duda

We construct a finitely generated solvable subgroup of Homeo(R) with a non-metaabelian characterizing quotient.

Group Theory · Mathematics 2020-07-29 Azer Akhmedov

Often a localization functor (in the category of groups) sends a finite simple group to another finite simple group. We study when such a localization also induces a localization between the automorphism groups and between the universal…

Algebraic Topology · Mathematics 2018-04-16 José L. Rodríguez , Jérôme Scherer , Antonio Viruel

We give an example of a symplectic manifold with a stable hypersurface such that nearby hypersurfaces are typically unstable.

Symplectic Geometry · Mathematics 2009-08-19 K. Cieliebak , U. Frauenfelder , G. P. Paternain

The class A of countable groups that admit a faithful, transitive, amenable -- in the sense that there is an invariant mean -- action on a set has been widely investigated in the past. In this paper, we no longer require the action to be…

Group Theory · Mathematics 2018-04-18 Claire Anantharaman-Delaroche

This paper is a survey, with few proofs, of ideas and notions related to self-similarity of groups, semi-groups and their actions. It attempts to relate these concepts to more familiar ones, such as fractals, self-similar sets, and…

Group Theory · Mathematics 2009-11-29 Laurent Bartholdi , Rostislav I. Grigorchuk , Volodymyr V. Nekrashevych

We define the notion of a semicharacter of a group G : A function from the group to C*, whose restriction to any abelian subgroup is a homomorphism. We conjecture that for any finite group, the order of the group of semicharacters is…

Group Theory · Mathematics 2013-11-12 Gil Alon

We prove that $Out(F_N)$ is boundary amenable. This also holds more generally for $Out(G)$, where $G$ is either a toral relatively hyperbolic group or a finitely generated right-angled Artin group. As a consequence, all these groups satisfy…

Group Theory · Mathematics 2021-01-21 Mladen Bestvina , Vincent Guirardel , Camille Horbez

We give an example of a finitely presented group $G$ with two non-$\pi_1$-equivalent asymptotic cones.

Group Theory · Mathematics 2007-05-23 A. Yu. Olshanskii , M. V. Sapir

Motivated by examples in infinite group theory, we classify the finite groups whose subgroups can never be decomposed as direct products.

Group Theory · Mathematics 2007-05-23 Ivan Marin

A Hom-group is the non-associative generalization of a group, whose associativity and unitality are twisted by a compatible bijective map. In this paper, we give some new examples of Hom-groups, and show the first and the second isomorphism…

Rings and Algebras · Mathematics 2020-12-15 Liangyun Chen , Tianqi Feng , Yao Ma , Ripan Saha , Hongyi Zhang

We define a relative property A for a countable group with respect to a finite family of subgroups. Many characterizations for relative property A are given. In particular a relative bounded cohomological characterization shows that if a…

Group Theory · Mathematics 2012-09-17 Ronghui Ji , Crichton Ogle , Bobby Ramsey