{ "id": "1202.3536", "version": "v2", "published": "2012-02-16T09:06:10.000Z", "updated": "2012-03-14T17:05:57.000Z", "title": "Distortion for diffeomorphisms of surfaces with boundary", "authors": [ "Kiran Parkhe" ], "comment": "13 pages. arXiv admin note: text overlap with arXiv:math/0404532", "categories": [ "math.DS" ], "abstract": "If $G$ is a finitely generated group with generators $\\{g_1,..., g_s\\}$, we say an infinite-order element $f \\in G$ is a distortion element of $G$ provided that $\\displaystyle \\liminf_{n \\to \\infty} \\frac{|f^n|}{n} = 0$, where $|f^n|$ is the word length of $f^n$ with respect to the given generators. Let $S$ be a compact orientable surface, possibly with boundary, and let $\\Diff(S)_0$ denote the identity component of the group of $C^1$ diffeomorphisms of $S$. Our main result is that if $S$ has genus at least two, and $f$ is a distortion element in some finitely generated subgroup of $\\Diff(S)_0$, then $\\supp(\\mu) \\subseteq \\Fix(f)$ for every $f$-invariant Borel probability measure $\\mu$. Under a small additional hypothesis the same holds in lower genus. For $\\mu$ a Borel probability measure on $S$, denote the group of $C^1$ diffeomorphisms that preserve $\\mu$ by $\\Diff_\\mu(S)$. Our main result implies that a large class of higher-rank lattices admit no homomorphisms to $\\Diff_{\\mu}(S)$ with infinite image. These results generalize those of Franks and Handel to surfaces with boundary.", "revisions": [ { "version": "v2", "updated": "2012-03-14T17:05:57.000Z" } ], "analyses": { "subjects": [ "37C85", "57M60", "22F10" ], "keywords": [ "diffeomorphisms", "invariant borel probability measure", "distortion element", "small additional hypothesis", "main result implies" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2012arXiv1202.3536P" } } }