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Related papers: Free nilpotent groups are C*-superrigid

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In this paper we explore a generic notion of superrigidity for von Neumann algebras $L(G)$ and reduced $C^*$-algebras $C^*_r(G)$ associated with countable discrete groups $G$. This allows us to classify these algebras for various new…

Operator Algebras · Mathematics 2021-07-16 Ionut Chifan , Alec Diaz-Arias , Daniel Drimbe

We provide lower estimates on the minimal number of generators of the profinite completion of free products of finite groups. In particular, we show that if C_1,...,C_n are finite cyclic groups then there exists a finite group G which is…

Group Theory · Mathematics 2007-05-23 Miklos Abert , Pal Hegedus

In this paper, using the topological interpretation of the Baer invariant of a group $G$, $\mathcal{V}M(G)$, with respect to an arbitrary variety $\mathcal{V}$, we extend a result of Burns and Ellis (Math. Z. 226 (1997) 405-428) on the…

Algebraic Topology · Mathematics 2014-04-04 Behrooz Mashayekhy , Hanieh Mirebrahimi , Zohreh Vasagh

An essentially free group action of $\Gamma$ on $(X,\mu)$ is called W*-superrigid if the crossed product von Neumann algebra $L^\infty(X) \rtimes \Gamma$ completely remembers the group $\Gamma$ and its action on $(X,\mu)$. We prove…

Operator Algebras · Mathematics 2023-07-11 Daniel Drimbe , Stefaan Vaes

In this paper we give a complete algebraic description of groups elementarily equivalent to a given free nilpotent group of finite rank.

Group Theory · Mathematics 2010-06-03 Alexei G. Myasnikov , Mahmood Sohrabi

In this paper we introduce an equivalence between the category of the t-nilpotent quadratic Lie algebras with d generators and the category of some symmetric invariant bilinear forms on the t-nilpotent free Lie algebra with d generators.…

Rings and Algebras · Mathematics 2017-01-13 Pilar Benito , Daniel de-la-Concepción , Jesús Laliena

Let $G$ be a finite group admitting a coprime automorphism $\alpha$. Let $J_G(\alpha)$ denote the set of all commutators $[x,\alpha]$, where $x$ belongs to an $\alpha$-invariant Sylow subgroup of $G$. We show that $[G,\alpha]$ is soluble or…

Group Theory · Mathematics 2022-11-02 Cristina Acciarri , Robert M. Guralnick , Pavel Shumyatsky

The paper is devoted to finding a homomorphic image for the $c$-nilpotent multiplier of the verbal product of a family of groups with respect to a variety ${\mathcal V}$ when ${\mathcal V} \subseteq {\mathcal N}_{c}$ or ${\mathcal…

Group Theory · Mathematics 2010-12-09 Azam Hokmabadi , Behrooz Mashayekhy

The homotopy symmetric $C^*$-algebras are those separable $C^*$-algebras for which one can unsuspend in E-theory. We find a new simple condition that characterizes homotopy symmetric nuclear $C^*$-algebras and use it to show that the…

Operator Algebras · Mathematics 2016-03-07 Marius Dadarlat , Ulrich Pennig

We prove that for many nonamenable groups \Gamma, including all hyperbolic groups and all nontrivial free products, the left-right wreath product group G := (Z/2Z)^(\Gamma) \rtimes (\Gamma \times \Gamma) is W*-superrigid. This means that…

Operator Algebras · Mathematics 2018-05-16 Mihaita Berbec , Stefaan Vaes

Let $A$ be an elementary abelian group of order $p^{k}$ with $k\geq 3$ acting on a finite $p'$-group $G$. The following results are proved. If $\gamma_{k-2}(C_{G}(a))$ is nilpotent of class at most $c$ for any $a\in A^{#}$, then…

Group Theory · Mathematics 2011-12-30 Cristina Acciarri , Pavel Shumyatsky

In this paper, we show that a locally graded group with a finite number m of non-(nilpotent of class at most n) subgroups is (soluble of class at most [log2(n)] + m + 3)-by-(finite of order $\le$ m!). Also we show that the derived length of…

Group Theory · Mathematics 2014-12-05 Mohammad Zarrin

Let $\mathfrak{Nil}$ be the class of nilpotent groups and $G$ be a group. We call $G$ a meta-$\mathfrak{Nil}$-Hamiltonian group if any of its non-$\mathfrak{Nil}$ subgroups is normal. Also, we call $G$ a para-$\mathfrak{Nil}$-Hamiltonian…

Group Theory · Mathematics 2024-02-21 Nasrin Dastborhan , Hamid Mousavi

In this paper, we work on the pro-nilpotent group topology of a free group. First we investigate the closure of the product of finitely many subgroups of a free group in the pro-nilpotent group topology. We present an algorithm for the…

Group Theory · Mathematics 2017-03-24 J. Almeida , M. H. Shahzamanian , B. Steinberg

We investigate to what extent a nilpotent Lie group is determined by its $C^*$-algebra. We prove that, within the class of exponential Lie groups, direct products of Heisenberg groups with abelian Lie groups are uniquely determined even by…

Operator Algebras · Mathematics 2019-09-05 Ingrid Beltita , Daniel Beltita

Let $G$ be a finite group and let $p$ be a prime. We continue the search for generic constructions of free products and free monoids in the unit group $\mathcal{U}(\mathbb{Z}G)$ of the integral group ring $\mathbb{Z}G$. For a nilpotent…

Rings and Algebras · Mathematics 2020-03-26 Geoffrey Janssens , Eric Jespers , Doryan Temmerman

Let L be a countable elementary language, N be a Fraisse limit. We consider free amalgamation for L-structures where L is arbitrary. If free amalgamation for finitely generated substructures exits in N, then it is a stationary independece…

Logic · Mathematics 2014-06-05 Andreas Baudisch

Motivated by the description of the C*-algebras of 5 dimensional nilpotent Lie groups as algebras of operator fields defined over their spectra, we introduce the family of C* -algebras with norm controlled dual limits and we show that the…

Group Theory · Mathematics 2013-09-27 Hedi Regeiba , Jean Ludwig

Let $G$ be an amenable group. We define and study an algebra $\mathcal{A}_{sn}(G)$, which is related to invariant means on the subnormal subgroups of $G$. For a just infinite amenable group $G$, we show that $\mathcal{A}_{sn}(G)$ is…

Group Theory · Mathematics 2021-09-07 Jared T. White

Let $G$ be an arbitrary group. We show that if the Fitting subgroup of $G$ is nilpotent then it is definable. We show also that the class of groups whose Fitting subgroup is nilpotent of class at most $n$ is elementary. We give an example…

Group Theory · Mathematics 2012-05-04 A. Ould Houcine