{ "id": "1103.5060", "version": "v2", "published": "2011-03-25T18:46:35.000Z", "updated": "2012-06-06T12:26:03.000Z", "title": "Bounded orbits and global fixed points for groups acting on the plane", "authors": [ "Kathryn Mann" ], "comment": "v2 reflects published version. Added argument in section 2, results unchanged", "journal": "Algebraic & Geometric Topology 12 (2012) 421-433", "doi": "10.2140/agt.2012.12.421", "categories": [ "math.DS", "math.GT" ], "abstract": "Let G be a group acting on the plane by orientation-preserving homeomorphisms. We show that if for some k>0 there is a ball of radius r > k/\\sqrt{3} such that each point x in the ball satisfies |gx -hx| < k for all g, h in G, and the action of G satisfies a nonwandering hypothesis, then the action has a global fixed point. In particular, any group of measure-preserving orientation preserving homeomorphisms of the plane with uniformly bounded orbits has a global fixed point. The constant k/\\sqrt{3} is sharp. We also show that a group acting on the plane with orbits bounded as above is left orderable.", "revisions": [ { "version": "v2", "updated": "2012-06-06T12:26:03.000Z" } ], "analyses": { "keywords": [ "global fixed point", "bounded orbits", "groups acting", "measure-preserving orientation preserving homeomorphisms", "ball satisfies" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2011arXiv1103.5060M" } } }