Zariski-dense deformations of standard discontinuous groups for pseudo-Riemannian homogeneous spaces

Kazuki Kannaka, Toshiyuki Kobayashi

Let $X=G/H$ be a homogeneous space of a Lie group $G$. When the isotropy subgroup $H$ is non-compact, a discrete subgroup $\hat{I}“$ may fail to act properly discontinuously on $X$. In t…