Paper detail

Every Infinite order mapping class has an infinite order action on the homology of some finite cover

We prove the following well known conjecture: let $Σ$ be an oriented surface of finite type whose fundamental group is a nonabelian free group. Let $ϕ\in \textup{Mod}(Σ)$ be a an infinite order mapping class. Then there exists a finite solvable cover $\widehatΣ \to Σ$, and a lift $\widehatϕ$ of $ϕ$ such that the action of $\widehatϕ$ on $H_1(\widehatΣ, \mathbb{Z})$ has infinite order. Our main tools are the theory of homological shadows, which was previously developed by the author, and Fourier analysis