{ "id": "1502.04339", "version": "v1", "published": "2015-02-15T17:58:11.000Z", "updated": "2015-02-15T17:58:11.000Z", "title": "Rigidity for group actions on homogeneous spaces by affine transformations", "authors": [ "Mohamed Bouljihad" ], "categories": [ "math.DS", "math.GR" ], "abstract": "We give a criterion for the rigidity of actions on homogeneous spaces. Let $G$ be a real Lie group, $\\Lambda$ a lattice in $G$, and $\\Gamma$ a subgroup of the affine group Aff$(G)$ stabilizing $\\Lambda$. Then the action of $\\Gamma$ on $G/\\Lambda$ has the rigidity property in the sense of S. Popa, if and only if the induced action of $\\Gamma$ on $\\mathbb{P}(\\frak{g})$ admits no $\\Gamma$-invariant probability measure, where $\\frak{g}$ is the Lie algebra of $G$. This generalizes results of M. Burger, and A. Ioana and Y. Shalom. As an application, we establish rigidity for the action of a class of groups acting by automorphisms on nilmanifolds associated to step 2 nilpotent Lie groups.", "revisions": [ { "version": "v1", "updated": "2015-02-15T17:58:11.000Z" } ], "analyses": { "keywords": [ "homogeneous spaces", "group actions", "affine transformations", "nilpotent lie groups", "real lie group" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv150204339B" } } }