English
Related papers

Related papers: Strongly dense free subgroups of semisimple algebr…

200 papers

We show that if a group is not virtually cyclic and is hyperbolic relative to a family of proper subgroups, then it has a hyperbolically embedded subgroup which contains a finitely generated non-abelian free group as a finite index…

Group Theory · Mathematics 2012-05-23 Yoshifumi Matsuda , Shin-ichi Oguni , Saeko Yamagata

In this paper we bring together results about the density of subsemigroups of abelian Lie groups, the minimal number of topological generators of abelian Lie groups and a result about actions of algebraic groups. We find the minimal number…

Functional Analysis · Mathematics 2011-08-05 Herbert Abels , Antonios Manoussos

The study of finite subgroups of a simple algebraic group $G$ reduces in a sense to those which are almost simple. If an almost simple subgroup of $G$ has a socle which is not isomorphic to a group of Lie type in the underlying…

Group Theory · Mathematics 2018-09-05 Alastair J. Litterick

A free semigroupoid algebra is the closure of the algebra generated by a TCK family of a graph in the weak operator topology. We obtain a structure theory for these algebras analogous to that of free semigroup algebra. We clarify the role…

Operator Algebras · Mathematics 2019-06-14 Kenneth R. Davidson , Adam Dor-On , Boyu Li

We investigate groups whose Cayley graphs have poor\-ly connected subgraphs. We prove that a finitely generated group has bounded separation in the sense of Benjamini--Schramm--Tim\'ar if and only if it is virtually free. We then prove a…

Group Theory · Mathematics 2020-11-09 David Hume , John M. Mackay

For any noncompact semisimple real Lie group $G$, we construct a group of affine transformations of its Lie algebra $\mathfrak{g}$ whose linear part is Zariski-dense in $\operatorname{Ad} G$ and which is free, nonabelian and acts properly…

Group Theory · Mathematics 2016-05-13 Ilia Smilga

For any right-angled Artin group, we show that its outer automorphism group contains either a finite-index nilpotent subgroup or a nonabelian free subgroup. This is a weak Tits alternative theorem. We find a criterion on the defining graph…

Group Theory · Mathematics 2009-10-27 Matthew B. Day

We formulate a strengthening of the Zariski dense orbit conjecture for birational maps of dynamical degree one. So, given a quasiprojective variety $X$ defined over an algebraically closed field $K$ of characteristic $0$, endowed with a…

Dynamical Systems · Mathematics 2022-02-15 Jason Bell , Dragos Ghioca

The complete algebraic structure of semisimple finite group algebra of a generalized strongly monomial group is provided. This work extends the work of Broche and del R{\'{\i}}o on strongly monomial groups. The theory is complimented by an…

Rings and Algebras · Mathematics 2018-12-20 Gurmeet K. Bakshi , Gurleen Kaur

We prove that every finitely generated Kleinian group that contains a finite, non-cyclic subgroup either is finite or virtually free or contains a surface subgroup. Hence, every arithmetic Kleinian group contains a surface subgroup.

Geometric Topology · Mathematics 2009-07-28 Marc Lackenby

We give new and improved results on the freeness of subgroups of free profinite groups: A subgroup containing the normal closure of a finite word in the elements of a basis is free; Every infinite index subgroup of a finitely generated…

Group Theory · Mathematics 2017-05-17 Mark Shusterman

Let $G$ be a simple algebraic group over an algebraically closed field $k$ and let $C_1, \ldots, C_t$ be non-central conjugacy classes in $G$. In this paper, we consider the problem of determining whether there exist $g_i \in C_i$ such that…

Group Theory · Mathematics 2020-04-13 Timothy C. Burness , Spencer Gerhardt , Robert M. Guralnick

We provide a new condition for an absolutely almost simple algebraic group to have good reduction with respect to a discrete valuation of the base field which is formulated in terms of the existence of maximal tori with special properties.…

Number Theory · Mathematics 2023-12-15 Vladimir I. Chernousov , Andrei S. Rapinchuk , Igor A. Rapinchuk

Without assuming the field structure on the additive group of real numbers $\mathbb{R}$ with the usual order $<,$ we explore the fact that every proper subgroup of $\mathbb{R}$ is either closed or dense. This property of subgroups of the…

Number Theory · Mathematics 2014-05-21 Jitender Singh

We present a new notion of non-positively curved groups: the collection of discrete countable groups acting (AU-)acylindrically on finite products of $\delta$-hyperbolic spaces with general type factors. Inspired by the classical theory of…

Group Theory · Mathematics 2025-12-30 Sahana Balasubramanya , Talia Fernos

Let $K$ be a field and let $\sigma$ be an automorphism and let $\delta$ be a $\sigma$-derivation of $K$. Then we show that the multiplicative group of nonzero elements of the division ring $D=K(x;\sigma,\delta)$ contains a free non-cyclic…

Rings and Algebras · Mathematics 2018-12-06 Jason P. Bell , Jairo Goncalves

Let S be a dense sub-semigroup of the positive real numbers, and let X be a separable, reflexive Banach space. This note contains a proof that every weakly continuous contractive semigroup of operators on X over S can be extended to a…

Functional Analysis · Mathematics 2009-03-21 Eliahu Levy , Orr Shalit

In this paper we give an alternative proof of Schreiber's theorem which says that an infinite discrete approximate subgroup in $\mathbb{R}^d$ is relatively dense around a subspace. We also deduce from Schreiber's theorem two new results.…

Dynamical Systems · Mathematics 2019-01-25 Alexander Fish

In this note, we study the problem on the existence of non-cyclic free subgroups of the skew group algebra of a locally finite group over a field.

Rings and Algebras · Mathematics 2020-11-04 Bui Xuan Hai , Cao Minh Nam , Mai Hoang Bien

We present a proof of the following claim. Suppose that $n$ is an integer such that $n>1$ and that $k$ is any field. Suppose that $g$ is an element of $\mathrm{SL}(n,k)$ of infinite order. Then the set $\{h\in\mathrm{SL}(n,k)\mid <g,h>$ is…

Group Theory · Mathematics 2014-11-06 Rupert McCallum