A Counterexample to the Deformation Conjecture For Uniform Tree Lattices
Ying-Sheng Liu · Proceedings of the American Mathematical Society · 1995
Let X be a universal cover of a finite connected graph. A uniform lattice on X is a group acting discretely and cocompactly on X. We provide a counterexample to Bass and Kulkarni’s Deformation Conjecture (1990) that a discrete subgroup $F \leq \operatorname {Aut} (X)$ could be deformed, outside some F-invariant subtree, into a uniform lattice.