The structure of doubly non-commuting isometries

Marcel de Jeu, Paulo R. Pinto

Suppose that $n\ge 1$ and that, for all $i$ and $j$ with $1\le i,j\le n$ and $i\ne j$, $z_{ij}\in \mathbb{T}$ are given such that $z_{ji}={\overline{z}}_{ij}$ for all $i\ne j$.…