Mutliple mixing and disjointness for time changes of bounded-type Heisenberg nilflows

Giovanni Forni, Adam Kanigowski

We study time changes of bounded type Heisenberg nilflows $({\varphi }_t)$ acting on the Heisenberg nilmanifold $M$. We show that for every positive $\tau \in W^s(M)$, $s>7/2$, every non-triv…