On the Zariski closure of the linear part of a properly discontinuous group of affine transformations
Let Gamma be a subgroup of the group of affine transformations of the affine space R2n+1. Suppose Gamma acts properly discontinuously on R2n+1. The paper deals with the question which subgroups of GL(2n + 1, R) occur as Zariski closure <(l(&UGamma;))over bar> of the linear part of such a group Gamma. The two main results of the paper say that SO (n + 1, n) does occur as <(l(&UGamma;))over bar> of such a group Gamma if n is odd, but does not if n is even.
60
2
315-344
315-344
LEHIGH UNIV