The geometry of the Eisenstein-Picard modular group
Falbel, Elisha ; Parker, John R.
Duke Math. J., Tome 131 (2006) no. 1, p. 249-289 / Harvested from Project Euclid
The Eisenstein-Picard modular group ${\rm PU}(2,1;\mathbb {Z}[\omega])$ is defined to be the subgroup of ${\rm PU}(2,1)$ whose entries lie in the ring $\mathbb {Z}[\omega]$ , where $\omega$ is a cube root of unity. This group acts isometrically and properly discontinuously on ${\bf H}^2_\mathbb{C}$ , that is, on the unit ball in $\mathbb {C}^2$ with the Bergman metric. We construct a fundamental domain for the action of ${\rm PU}(2,1;\mathbb {Z}[\omega])$ on ${\bf H}^2_\mathbb {C}$ , which is a 4-simplex with one ideal vertex. As a consequence, we elicit a presentation of the group (see Theorem 5.9). This seems to be the simplest fundamental domain for a finite covolume subgroup of ${\rm PU}(2,1)$
Publié le : 2006-02-01
Classification:  22E40,  11F60
@article{1137077885,
     author = {Falbel, Elisha and Parker, John R.},
     title = {The geometry of the Eisenstein-Picard modular group},
     journal = {Duke Math. J.},
     volume = {131},
     number = {1},
     year = {2006},
     pages = { 249-289},
     language = {en},
     url = {http://dml.mathdoc.fr/item/1137077885}
}
Falbel, Elisha; Parker, John R. The geometry of the Eisenstein-Picard modular group. Duke Math. J., Tome 131 (2006) no. 1, pp.  249-289. http://gdmltest.u-ga.fr/item/1137077885/