Rigidity of braid group actions on $\mathbb{R}$ and of low-genus mapping class group actions on $S^1$

Idrissa Ba, Adam Clay, Tyrone Ghaswala

Every nontrivial action of the braid group $B_n$ on $\mathbb{R}$ by orientation-preserving homeomorphisms yields, up to conjugation by a homeomorphism of $\mathbb{R}$, a representa…