Rigidity of Kleinian groups via self-joinings: measure theoretic criterion

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Kim, Dongryul M., Oh, Hee
Formato: Preprint
Publicado: 2023
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866915452233449472
author Kim, Dongryul M.
Oh, Hee
author_facet Kim, Dongryul M.
Oh, Hee
contents Let $n, m\ge 2$. Let $Γ<\text{SO}^\circ(n+1,1)$ be a Zariski dense convex cocompact subgroup and $Λ\subset\mathbb{S}^n$ be its limit set. Let $ρ: Γ\to \text{SO}^\circ(m+1,1)$ be a Zariski dense convex cocompact faithful representation and $f:Λ\to \mathbb{S}^{m}$ the $ρ$-boundary map. Let $$Λ_f:= \bigcup \left\{ C \cap Λ: \begin{matrix} C \subset \mathbb{S}^n \text{ is a circle such that} \\ f(C \cap Λ) \text{ is contained in a proper sphere } \text{in } \mathbb{S}^m \end{matrix} \right\}.$$ When there exists at least one $Λ$-doubly stable circle in $\mathbb{S}^n$ (e.g., $Ω=\mathbb{S}^n-Λ$ is disconnected), we prove the following dichotomy: $$\text{either}\quad Λ_f= Λ\quad \text{ or } \quad \mathcal{H}^δ(Λ_f) =0,$$ where $\mathcal{H}^δ$ is the Hausdorff measure of dimension $δ=\dim_H Λ$. Moreover, in the former case, we have $n=m$ and $ρ$ is a conjugation by a Möbius transformation on $\mathbb{S}^n$. Our proof uses ergodic theory for directional diagonal flows and conformal measure theory of discrete subgroups of higher rank semisimple Lie groups, applied to the self-joining subgroup $Γ_ρ=(\operatorname{id} \times ρ)(Γ) < \text{SO}^\circ(n+1,1)\times \text{SO}^\circ(m+1,1)$. We also obtain an analogous theorem for any divergence-type subgroup.
format Preprint
id arxiv_https___arxiv_org_abs_2302_03552
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Rigidity of Kleinian groups via self-joinings: measure theoretic criterion
Kim, Dongryul M.
Oh, Hee
Geometric Topology
Dynamical Systems
Group Theory
Let $n, m\ge 2$. Let $Γ<\text{SO}^\circ(n+1,1)$ be a Zariski dense convex cocompact subgroup and $Λ\subset\mathbb{S}^n$ be its limit set. Let $ρ: Γ\to \text{SO}^\circ(m+1,1)$ be a Zariski dense convex cocompact faithful representation and $f:Λ\to \mathbb{S}^{m}$ the $ρ$-boundary map. Let $$Λ_f:= \bigcup \left\{ C \cap Λ: \begin{matrix} C \subset \mathbb{S}^n \text{ is a circle such that} \\ f(C \cap Λ) \text{ is contained in a proper sphere } \text{in } \mathbb{S}^m \end{matrix} \right\}.$$ When there exists at least one $Λ$-doubly stable circle in $\mathbb{S}^n$ (e.g., $Ω=\mathbb{S}^n-Λ$ is disconnected), we prove the following dichotomy: $$\text{either}\quad Λ_f= Λ\quad \text{ or } \quad \mathcal{H}^δ(Λ_f) =0,$$ where $\mathcal{H}^δ$ is the Hausdorff measure of dimension $δ=\dim_H Λ$. Moreover, in the former case, we have $n=m$ and $ρ$ is a conjugation by a Möbius transformation on $\mathbb{S}^n$. Our proof uses ergodic theory for directional diagonal flows and conformal measure theory of discrete subgroups of higher rank semisimple Lie groups, applied to the self-joining subgroup $Γ_ρ=(\operatorname{id} \times ρ)(Γ) < \text{SO}^\circ(n+1,1)\times \text{SO}^\circ(m+1,1)$. We also obtain an analogous theorem for any divergence-type subgroup.
title Rigidity of Kleinian groups via self-joinings: measure theoretic criterion
topic Geometric Topology
Dynamical Systems
Group Theory
url https://arxiv.org/abs/2302.03552