Nondivergence on homogeneous spaces and rigid totally geodesics

负曲率中全测地超曲面的刚性

Rigidity of Totally Geodesic Hypersurfaces in Negative Curvature

本文研究负曲率流形中全测地超曲面在体积最小化等号情形下是否迫使流形等距，证明许多超曲面具有刚性，并构造反例。

凸核中全测地子流形的正常性与有限性

Properness and finiteness of totally geodesic submanifolds in the convex core

本文研究几何有限秩一局部对称流形凸核内的全测地子流形，证明其凸核内维数≥2的极大全测地子流形正常浸入、体积有限且数量有限，结合已有工作推导得出含无穷多该类子流形的对应流形必为算术流形。

Measurable Rigidity for Kleinian groups

Let $G, H$ be two Kleinian groups with homeomorphic quotients $\mathbb H^3/G$ and $\mathbb H^3/H$. We assume that $G$ is of divergence type, and consider the Patterson-Sullivan measures of $G$ and $H$. The measurable rigidity theorem by Sullivan and Tukia says that a measurable and essentially directly measurable equivariant boundary map $\widehat k$ from the limit set $Λ_G$ of $G$ to that of $H$ is either the restriction of a Möbius transformation or totally singular. In this paper, we shall show that such $\widehat k$ always exists. In fact, we shall construct $\widehat k$ concretely from th…

黎曼曲面模空间中全测地子簇的几何

The geometry of totally geodesic subvarieties of moduli spaces of Riemann surfaces

该论文证明了黎曼曲面模空间中全测地子簇边界的半单性，并据此证明了相关Teichmüller子流形和轨道基本群是层次双曲的，为这些对象提供了新工具。

Rigidity, lattices and invariant measures beyond homogeneous dynamics

This article discusses two recent works by the author, one with Brown and Hurtado on Zimmer's conjecture and one with Bader, Miller and Stover on totally geodesic submanifolds of real and complex hyperbolic manifolds. The main purpose of juxtaposing these two very disparate sets of results in one article is to emphasize a common aspect: that the study of invariant and partially invariant measures outside the homogeneous setting is important to questions about rigidity in geometry and dynamics. I will also discuss some open questions including some that seem particularly compelling in light of …

Geodesic Planes in Geometrically Finite Manifolds

We study the problem of rigidity of closures of totally geodesic plane immersions in geometrically finite manifolds containing rank $1$ cusps. We show that the key notion of K-thick recurrence of horocycles fails generically in this setting. This property was introduced in the recent work of McMullen, Mohammadi and Oh. Nonetheless, in the setting of geometrically finite groups whose limit sets are circle packings, we derive 2 density criteria for non-closed geodesic plane immersions, and show that closed immersions give rise to surfaces with finitely generated fundamental groups. We also obtai…