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Related papers: On Tarski's problem for virtually free groups

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A group is SimpHAtic if it acts geometrically on a simply connected simplicially hereditarily aspherical (SimpHAtic) complex. We show that finitely presented normal subgroups of the SimpHAtic groups are either: finite, or of finite index,…

Group Theory · Mathematics 2021-09-29 Damian Osajda

We study groups having the property that every non-abelian subgroup is equal to its normalizer. This class of groups is closely related to an open problem posed by Berkovich. We give a full classification of finite groups having the above…

Group Theory · Mathematics 2016-10-21 Costantino Delizia , Urban Jezernik , Primoz Moravec , Chiara Nicotera

We present an algorithm that decides whether a finitely generated linear group over an infinite field is solvable-by-finite: a computationally effective version of the Tits alternative. We also give algorithms to decide whether the group is…

Group Theory · Mathematics 2019-05-15 A. S. Detinko , D. L. Flannery , E. A. O'Brien

We provide an algorithm that, given a finite set of generators for a subgroup $H$ of a finitely generated free group $F$, determines whether $H$ is echelon or not and, in case of affirmative answer, also computes a basis with respect to…

Group Theory · Mathematics 2023-11-07 Dario Ascari

We generalize the classical definition of effectively closed subshift to finitely generated groups. We study classical stability properties of this class and then extend this notion by allowing the usage of an oracle to the word problem of…

Group Theory · Mathematics 2019-04-26 Nathalie Aubrun , Sebastián Barbieri , Mathieu Sablik

This paper investigates the asymptotic behaviour of the minimal number of generators of finite index subgroups in residually finite groups. We analyze three natural classes of groups: amenable groups, groups possessing an infinite soluble…

Group Theory · Mathematics 2011-02-16 Miklos Abert , Andrei Jaikin-Zapirain , Nikolay Nikolov

Given a finite abelian group $G$ and elements $x, y \in G$, we prove that there exists $\phi \in \text{Aut}(G)$ such that $\phi(x) = y$ if and only if $G/\langle x \rangle \cong G/\langle y \rangle$. This result leads to our development of…

Group Theory · Mathematics 2025-12-23 Arjun Agarwal , Rachel Chen , Rohan Garg , Jared Kettinger

(1) There is a finitely presented group with a word problem which is a uniformly effectively inseparable equivalence relation. (2) There is a finitely generated group of computable permutations with a word problem which is a universal…

Logic · Mathematics 2016-09-13 André Nies , Andrea Sorbi

If $G$ is a group, a virtual retract of $G$ is a subgroup which is a retract of a finite index subgroup. Most of the paper focuses on two group properties: property (LR), that all finitely generated subgroups are virtual retracts, and…

Group Theory · Mathematics 2019-10-09 Ashot Minasyan

We characterize when a generalized Baumslag-Solitar group is linear, and extend the result to the fundamental groups of a graph of groups with infinite virtually cyclic vertex and edge groups.

Group Theory · Mathematics 2026-05-27 Hsuan-Yu Wang

In 1960 Fuchs posed the problem of characterizing the groups which are the groups of units of commutative rings. In the following years, some partial answers have been given to this question in particular cases. In this paper we address…

Rings and Algebras · Mathematics 2019-08-07 Ilaria Del Corso

A generalized Baumslag-Solitar group (GBS group) is a finitely generated group $G$ which acts on a tree with all edge and vertex stabilizers infinite cyclic. We show that Out(G) either contains non-abelian free groups or is virtually…

Group Theory · Mathematics 2014-11-11 Gilbert Levitt

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

In 2006 Z. Sela and independently O. Kharlampovich and A. Myasnikov gave a solution to the Tarski problems by showing that two non-abelian free groups have the same elementary theory. Subsequently Z. Sela generalized the techniques used in…

Group Theory · Mathematics 2018-11-16 Simon Heil

Ordering theorems, characterizing when partial orders of a group extend to total orders, are used to generate hypersequent calculi for varieties of lattice-ordered groups (l-groups). These calculi are then used to provide new proofs of…

Logic · Mathematics 2017-08-03 Almudena Colacito , George Metcalfe

We discuss various methods and their effectiveness for solving linear equations over finitely generated abelian groups. More precisely, if $\varphi\colon G\to H$ is a homomorphism of finitely generated abelian groups and $b\in H$, we…

Group Theory · Mathematics 2010-07-16 René Hartung

We prove that all finitely generated fully residually free groups (limit groups) have a sequence of finite dimensional unitary representations that `strongly converge' to the regular representation of the group. The corresponding statement…

Group Theory · Mathematics 2023-01-18 Larsen Louder , Michael Magee with Appendix by Will Hide , Michael Magee

The Andrews-Curtis conjecture remains one of the outstanding open problems in combinatorial group theory. It claims that every normally generating $r$-tuple of a free group $F_r$ of rank $r\geq 2$ can be reduced to a basis by means of…

Group Theory · Mathematics 2023-05-22 Vitaly Roman'kov

It is shown that every accessible group which is integrable orbit equivalent to a free group is virtually free. Moreover, we also show that any integrable orbit-equivalence between finitely generated groups extends to their end…

Dynamical Systems · Mathematics 2016-01-05 Lewis Bowen

We adapt methods from quiver representation theory and Hall algebra techniques to the counting of representations of virtually free groups over finite fields. This gives rise to the computation of the E-polynomials of…

Representation Theory · Mathematics 2022-01-31 Fabian Korthauer