58 citations · 221 across the 38 of their papers we have counts for
43 papers
Greenberg-Shalom's Commensurator Hypothesis and Applications
Nic Brody, David Fisher, Mahan Mj +1
We discuss many surprising implications of a positive answer to a question raised in some cases by Greenberg in the s and more generally by Shalom in the early s. We ref…
A Tukia-type theorem for nilpotent Lie groups and quasi-isometric rigidity of solvable groups
Tullia Dymarz, David Fisher, Xiangdong Xie
In this paper we study uniform quasiconformal groups of Carnot-by-Carnot groups. We show that they can be conjugated into conformal groups provided the induced action on the space…
Smooth and analytic actions of and on closed -dimensional manifolds
David Fisher, Karin Melnick
The main result is a classification of smooth actions of , , or connected groups locally isomorphic to it, on closed -manifolds, extending a theorem of…
A new proof of finiteness of maximal arithmetic reflection groups
David Fisher, Sebastian Hurtado
We give a new proof of the finiteness of maximal arithmetic reflection groups. Our proof is novel in that it makes no use of trace formulas or other tools from the theory of automo…
Commensurators of normal subgroups of lattices
David Fisher, Mahan Mj, Wouter Van Limbeek
We study a question of Greenberg-Shalom concerning arithmeticity of discrete subgroups of semisimple Lie groups with dense commensurators. We answer this question positively for no…
Rigidity, lattices and invariant measures beyond homogeneous dynamics
David Fisher
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 r…