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Related papers: Fra\"iss\'e limits of limit groups

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Every finite non-abelian group of order $n$ has a non-central element whose centralizer has order exceeding $n^{1/3}$. The proof does not rely on the classification of finite simple groups, yet it uses the Feit-Thompson theorem.

Group Theory · Mathematics 2020-07-23 Daniel Palacín

We demonstrate the existence of a family of finitely generated subgroups of Richard Thompson's group $F$ which is strictly well-ordered by the embeddability relation in type $\epsilon_0 +1$. All except the maximum element of this family…

Group Theory · Mathematics 2021-02-09 Collin Bleak , Matthew G. Brin , Justin Tatch Moore

We give a systematic study of the model theory of generic nilpotent groups and Lie algebras. We show that the Fra\"iss\'e limit of 2-nilpotent groups of exponent $p$ studied by Baudisch is 2-dependent and NSOP$_{1}$. We prove that the class…

Logic · Mathematics 2024-06-24 Christian d'Elbée , Isabel Müller , Nicholas Ramsey , Daoud Siniora

We show that for every positive integer $n$ there exists a simple group that is of type $\mathrm{F}_{n-1}$ but not of type $\mathrm{F}_n$. For $n\ge 3$ these groups are the first known examples of this kind. They also provide infinitely…

Group Theory · Mathematics 2018-10-23 Rachel Skipper , Stefan Witzel , Matthew C. B. Zaremsky

We study groups having the property that every non-abelian subgroup contains its centralizer. We describe various classes of infinite groups in this class, and address a problem of Berkovich regarding the classification of finite $p$-groups…

Group Theory · Mathematics 2016-06-07 Costantino Delizia , Heiko Dietrich , Primoz Moravec , Chiara Nicotera

In this paper we show that there exists an uncountable family of finitely generated simple groups with the same positive theory as any non-abelian free group. In particular, these simple groups have infinite $w$-verbal width for all…

A new class of groups $\mathcal{C}$, containing all coherent RAAGs and all toral relatively hyperbolic groups, is defined. It is shown that, for a group $G$ in the class $\mathcal{C}$, the $\mathbb{Z}[t]$-exponential group…

Group Theory · Mathematics 2022-01-26 Montserrat Casals-Ruiz , Andrew Duncan , Ilya Kazachkov

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

Sacerdote [Sa] has shown that the non-Abelian free groups satisfy precisely the same universal-existential sentences Th(F$_2$)$\cap \forall \exists $ in a first-order language L$_o$ appropriate for group theory. It is shown that in every…

Group Theory · Mathematics 2009-09-25 Anthony Gaglione , Dennis Spellman

A countable group is C*-simple if its reduced C*-algebra is a simple algebra. Since Powers recognised in 1975 that non-abelian free groups are C*-simple, large classes of groups which appear naturally in geometry have been identified,…

Operator Algebras · Mathematics 2007-05-23 Pierre de la Harpe

We give upper bounds for triples of subsets of a finite group such that the triples of elements that multiply to 1 form a perfect matching. Our bounds are the first to give exponential savings in powers of an arbitrary finite group.…

Combinatorics · Mathematics 2017-02-06 Will Sawin

We study the algebraic entropy of continuous endomorphisms of compactly covered, locally compact, topologically quasihamiltonian groups. We provide a Limit-free formula which helps us to simplify the computations of this entropy. Moreover,…

Dynamical Systems · Mathematics 2019-05-08 Wenfei Xi , Menachem Shlossberg , Daniele Toller

We give a simple proof of the finite presentation of Sela's limit groups by using free actions on R^n-trees. We first prove that Sela's limit groups do have a free action on an R^n-tree. We then prove that a finitely generated group having…

Group Theory · Mathematics 2014-11-11 Vincent Guirardel

We classify up to coarse equivalence all countable abelian groups of finite torsion free rank. The Q-cohomological dimension and the torsion free rank are the two invariants that give us such classification. We also prove that any countable…

Group Theory · Mathematics 2008-03-05 J. Higes

We study in this paper some connections between the Fraisse theory of amalgamation classes and ultrahomogeneous structures, Ramsey theory, and topological dynamics of automorphism groups of countable structures.

Logic · Mathematics 2007-09-03 A. S. Kechris , V. G. Pestov , S. Todorcevic

In this talk I first review at an elementary level a selection of central limit theorems, including some lesser known cases, for sums and maxima of uncorrelated and correlated random variables. I recall why several of them appear in…

Statistical Mechanics · Physics 2010-08-26 H. J. Hilhorst

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

We reformulate several basic notions of notions in finite group theory in terms of iterations of the lifting property (orthogonality) with respect to particular morphisms. Our examples include the notions being nilpotent, solvable, perfect,…

Group Theory · Mathematics 2019-06-06 Misha Gavrilovich

Suppose $G$ is a $\mathcal{T}$-group (finitely generated torsion-free nilpotent) with centralizers outside of the derived subgroup being abelian of rank equal to $\text{rank}(Z_1)+1$. This includes the class of free nilpotent groups…

Group Theory · Mathematics 2024-09-25 Adam Moubarak

In this paper, we give a self-contained and quite elementary proof that the class of all dimension drop algebras together with their distinguished faithful traces forms a Fra\"iss\'e class with the Jiang-Su algebra as its limit. We also…

Operator Algebras · Mathematics 2016-02-02 Shuhei Masumoto