Homomorphic images of Branch groups, and Serre's property (FA)
arXiv:0704.2572
Abstract
It is shown that a finitely generated branch group has Serre's property (FA) if and only if it does not surject onto the infinite cyclic group or the infinite dihedral group. An example of a finitely generated self-similar branch group surjecting onto the infinite cyclic group is constructed.
20 pages, 2 figures