Lattices in SU(2,1) can be viewed in several different ways: via their geometry as holomorphic complex hyperbolic isometries, as monodromy groups of hypergeometric functions, via algebraic geometry as ball quotients and (sometimes) using arithmeticity. In this talk I will describe these different points of view using examples constructed by Deligne and Mostow and by Deraux, Paupert and myself.
22E40 ; 20F05 ; 20F36 ; 32M25