论文标题
通过真实线的同态近似近似非亚伯自由组
Approximating nonabelian free groups by groups of homeomorphisms of the real line
论文作者
论文摘要
We show that for a large class $\mathcal{C}$ of finitely generated groups of orientation preserving homeomorphisms of the real line, the following holds: Given a group $G$ of rank $k$ in $\mathcal{C}$, there is a sequence of $k$-markings $(G, S_n), n\in \mathbf{N}$ whose limit in the space of marked groups是带有标准标记的排名$ k $的免费组。我们认为的班级由接受满足轻度动态条件的行动和某些“自相似性”类型假设组成。例子包括汤普森(Thompson)的$ f $,希格曼·汤普森(Higman-Thompson)小组,斯坦 - 汤普森(Stein-Thompson)小组,各种比埃里·斯特雷贝尔(Bieri-Strebel)小组,黄金比率汤普森(Thompson Group),以及有限的一组分段投影型同构同构。对于汤普森(Thompson)的组$ f $,我们提供了一个新的,更简单的证明,证明了布林(Groups,Goem,几何和Dynamics 2010)证明了这一事实。
We show that for a large class $\mathcal{C}$ of finitely generated groups of orientation preserving homeomorphisms of the real line, the following holds: Given a group $G$ of rank $k$ in $\mathcal{C}$, there is a sequence of $k$-markings $(G, S_n), n\in \mathbf{N}$ whose limit in the space of marked groups is the free group of rank $k$ with the standard marking. The class we consider consists of groups that admit actions satisfying mild dynamical conditions and a certain "self-similarity" type hypothesis. Examples include Thompson's group $F$, Higman-Thompson groups, Stein-Thompson groups, various Bieri-Strebel groups, the golden ratio Thompson group, and finitely presented non amenable groups of piecewise projective homeomorphisms. For the case of Thompson's group $F$ we provide a new and considerably simpler proof of this fact proved by Brin (Groups, Geometry, and Dynamics 2010).