103 citations · 264 across the 55 of their papers we have counts for
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math.GR2019★ 2 cited
Algebraic Structure of Diffeomorphism Groups of One-Manifolds
Jaewon Chang, Sang-hyun Kim, Thomas Koberda
It is a celebrated result of Mather that the group of --diffeomorphisms of an --manifold is simple, provided that a mild isotopy condition is satisfied, with the possible e…
math.GR2019★ 1 cited
An effective Lie--Kolchin theorem for quasi-unipotent matrices
Thomas Koberda, Feng Luo, Hongbin Sun
We establish an effective version of the classical Lie--Kolchin Theorem. Namely, let be quasi--unipotent matrices such that the Jordan Canonical F…
math.GR2019
Non-freeness of groups generated by two parabolic elements with small rational parameters
Sang-hyun Kim, Thomas Koberda
Let , let \[a=\begin{pmatrix} 1&0\\1&1\end{pmatrix},\quad b_q=\begin{pmatrix} 1&q\\0&1\end{pmatrix},\] and let be the group generate…