Smoothing nilpotent actions on 1-manifolds

Kiran Parkhe

Let $M$ be a connected 1-manifold, i.e., $M=\mathbb{R}\cong (0,1),[0,1),[0,1]$, or $S^1$, and let $\Homeo_+(M)$ (resp. $\Diff_+^1(M)$) be the group of orientation-preserving homeom…