We provide a concrete criterion to determine whether or not two given elements of PU.2; 1/ can bewritten as products of real reflections,with one reflection in common. As an application, we show that the Picardmodular groups PU(2, 1,Od)with d = 1, 2, 3, 7, 11 are generated by real reflections up to index 1, 2, 4 or 8.
- Complex hyperbolic geometry
- Reflection groups
ASJC Scopus subject areas
- Geometry and Topology
- Discrete Mathematics and Combinatorics