paper

Parabolic perturbations of unipotent flows on compact quotients of

arXiv:1711.04821

Abstract

We consider a family of smooth perturbations of unipotent flows on compact quotients of which are not time-changes. More precisely, given a unipotent vector field, we perturb it by adding a non-constant component in a commuting direction. We prove that, if the resulting flow preserves a measure equivalent to Haar, then it is parabolic and mixing. The proof is based on a geometric shearing mechanism together with a non-homogeneous version of Mautner Phenomenon for homogeneous flows. Moreover, we characterize smoothly trivial perturbations and we relate the existence of non-trivial perturbations to the failure of cocycle rigidity of parabolic actions in .

16 pages, 2 figures

References in corpus (1)