A real convexity theorem for quasi-hamiltonian actions
| dc.creator | Schaffhauser, Florent | |
| dc.date | 2007-05-07 | |
| dc.date.accessioned | 2026-07-07T07:59:46Z | |
| dc.date.available | 2026-07-07T07:59:46Z | |
| dc.description | The main result of this paper is a quasi-hamiltonian analogue of a special case of the O'Shea-Sjamaar convexity theorem for usual momentum maps. We denote by U a simply connected compact connected Lie group and we fix an involutive automorphism of maximal rank on this Lie group (such an automorphism always exists). We then denote by M a quasi-hamiltonian U-space and we prove that the image under the momentum map of the fixed-point set of a form-reversing compatible involution of M is a convex polytope, which is in fact equal to the full momentum polytope. This theorem was announced in arXiv:math/0609517v1. As an application, we obtain an example of lagrangian subspace in representation spaces of surface groups. | |
| dc.description | 25 pages | |
| dc.identifier | https://arxiv.org/abs/0705.0858 | |
| dc.identifier | http://arxiv.org/abs/0705.0858 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/128491 | |
| dc.subject | Symplectic Geometry | |
| dc.subject | 53D20 | |
| dc.title | A real convexity theorem for quasi-hamiltonian actions | |
| dc.type | text |