Lorentzian Kleinian groups

  title={Lorentzian Kleinian groups},
  author={C. Clare Frances},
In this article we introduce some basic tools for the study of Lorentzian Kleinian groups. These groups are discrete subgroups of the Lorentzian M\"obius group $O(2,n)$, acting properly discontinuously on some nonempty open subset of Einstein's universe, the Lorentzian analogue of the conformal sphere.