A proof of the Elliott-R\'{o}dl conjecture on hypertrees in Steiner triple systems

Hypertrees are linear hypergraphs where every two vertices are connected by a unique path. Elliott and R\"{o}dl conjectured that for any given $\mu>0$, there exists $n_0$ such that the following holds. Every $n$-vertex Steiner triple system contains all hypertrees with at most $(1-\mu)n$ vertices whenever $n\geq n_0$. We prove this conjecture.
Comment: 19 pages, 2 figures