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Related papers: On \omega-categorical, generically stable groups

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Let $\Gamma_g$ denote the orientation-preserving Mapping Class Group of the genus $g\geq 1$ closed orientable surface. In this paper we show that for fixed $g$, every finite group occurs as a quotient of a finite index subgroup of…

Geometric Topology · Mathematics 2014-11-11 Gregor Masbaum , Alan W. Reid

We study the groups $G$ with the curious property that there exists an element $k\in G$ and a function $f\colon G\to G$ such that $f(xk)=xf(x)$ holds for all $x\in G$. This property arose from the study of near-rings and input-output…

Group Theory · Mathematics 2022-02-11 Dominik Bernhardt , Tim Boykett , Alice Devillers , Johannes Flake , S. P. Glasby

We prove that if $(H,G)$ is a small, $nm$-stable compact $G$-group, then $H$ is nilpotent-by-finite, and if additionally $\NM(H) \leq \omega$, then $H$ is abelian-by-finite. Both results are significant steps towards the proof of the…

Logic · Mathematics 2011-10-04 Krzysztof Krupinski , Frank Olaf Wagner

Let $G$ be a finite group and $\sigma_1(G)=\frac{1}{|G|}\sum_{H\leq G}\,|H|$. In this paper, we prove that if $\sigma_1(G)<2+\frac{11}{|G|}$\,, then $G$ is supersolvable. In particular, some new characterizations of the well-known groups…

Group Theory · Mathematics 2021-02-16 Marius Tărnăuceanu

In 1968, John Thompson proved that a finite group $G$ is solvable if and only if every $2$-generator subgroup of $G$ is solvable. In this paper, we prove that solvability of a finite group $G$ is guaranteed by a seemingly weaker condition:…

Group Theory · Mathematics 2010-08-02 Silvio Dolfi , Marcel Herzog , Cheryl E. Praeger

Let $G$ be a finite group and $\sigma_1(G)=\frac{1}{|G|}\sum_{H\leq G}\,|H|$. In this note, we prove that if $\sigma_1(G)<\frac{117}{20}$, then $G$ is solvable. Moreover, we have $\sigma_1(G)=\frac{117}{20}$ if and only if $G\cong A_5$.…

Group Theory · Mathematics 2019-08-13 Marius Tărnăuceanu

We prove that $\ omega $-categorical dp-minimal groups are nilpotent-by-finite. We also show that in dp-minimal definably amenable groups, f-generic global types are strongly f-generic.

Logic · Mathematics 2017-05-08 Elad Levi , Itay Kaplan , Pierre Simon

We show that for any $n\geq 3$ the theory of open generalized $n$-gons is complete, decidable and strictly stable, yielding a new class of examples in the zoo of stable theories.

Logic · Mathematics 2023-10-03 Anna-Maria Ammer , Katrin Tent

We prove that all invariant random subgroups of the lamplighter group $L$ are co-sofic. It follows that $L$ is permutation stable, providing an example of an infinitely presented such a group. Our proof applies more generally to all…

Group Theory · Mathematics 2019-11-27 Arie Levit , Alexander Lubotzky

The following theorem is proved: Let $G$ be a finite group and $\pi_e(G)$ be the set of element orders in $G$. If $\pi_e(G) \cap \{2\}=\emptyset$; or $\pi_e(G) \cap \{3, 4\}=\emptyset$; or $\pi_e(G) \cap \{3,5\}=\emptyset$, then $G$ is…

Group Theory · Mathematics 2017-04-06 Wujie Shi

The solvability of monomial groups is a well-known result in character theory. Certain properties of Artin L-series suggest a generalization of these groups, namely to such groups where every irreducible character has some multiple which is…

Group Theory · Mathematics 2021-02-17 Joachim König

Using algebraic geometry methods, the third author proved that the group ring of a surjunctive group with coefficients in a field is always stably finite. In other words, every group satisfying Gottschalk's conjecture also satisfies…

Group Theory · Mathematics 2023-11-07 Tullio Ceccherini-Silberstein , Michel Coornaert , Xuan Kien Phung

In this paper, we will show that if for every nonlinear complex irreducible character of a finite group G, some multiple of it is induced from an irreducible character of some proper subgroup of G, then G is solvable. This is a…

Group Theory · Mathematics 2012-11-09 Tung Le , Jamshid Moori , Hung P. Tong-Viet

Let $G$ be a definable group in a $p$-adically closed field $M$. We show that $G$ has finitely satisfiable generics (fsg) if and only if $G$ is definably compact. The case $M = \mathbb{Q}_p$ was previously proved by Onshuus and Pillay.

Logic · Mathematics 2022-03-30 Will Johnson

We prove that in every finitely generated profinite group, every subgroup of finite index is open; this implies that the topology on such groups is determined by the algebraic structure. This is deduced from the main result about finite…

Group Theory · Mathematics 2007-05-23 Nikolay Nikolov , Dan Segal

It is proved that all finitely generated subgroups of generalized free product of two groups are finitely separable provided that free factors have this property and amalgamated subgroups are normal in corresponding factors and satisfy the…

Group Theory · Mathematics 2013-08-20 David Moldavanskii , Anastasiya Uskova

In this note we prove that every finitely presented subgroup of a systolic group is itself systolic.

Group Theory · Mathematics 2013-07-16 Gašper Zadnik

We prove that in a continuous $\aleph_0$-stable theory every type-definable group is definable. The two main ingredients in the proof are: \begin{enumerate} \item Results concerning Morley ranks (i.e., Cantor-Bendixson ranks) from…

Logic · Mathematics 2014-02-10 Itaï Ben Yaacov

Let G be a finite group. Denote by \psi(G) the sum \psi(G)=\sum_{x\in G}|x| where |x| denotes the order of the element x, and by o(G) the quotient o(G)=\frac{\psi(G)}{|G|}. Confirming a conjecture posed by E.I. Khukhro, A. Moreto and M.…

Group Theory · Mathematics 2021-12-09 M. Herzog , P. Longobardi , M. Maj

We study finite groups $G$ with the property that for any subgroup $M$ maximal in $G$ whose order is divisible by all the prime divisors of $|G|$, $M$ is supersolvable. We show that any nonabelian simple group can occur as a composition…

Group Theory · Mathematics 2020-11-24 Alexander Moretó