{ "id": "math/0409528", "version": "v1", "published": "2004-09-27T16:55:43.000Z", "updated": "2004-09-27T16:55:43.000Z", "title": "Magnetic Rigidity of Horocycle flows", "authors": [ "Gabriel P. Paternain" ], "categories": [ "math.DS", "math.DG" ], "abstract": "Let $M$ be a closed oriented surface endowed with a Riemannian metric $g$ and let $\\Omega$ be a 2-form. We show that the magnetic flow of the pair $(g,\\Omega)$ has zero asymptotic Maslov index and zero Liouville action if and only $g$ has constant Gaussian curvature, $\\Omega$ is a constant multiple of the area form of $g$ and the magnetic flow is a horocycle flow. This characterization of horocycle flows implies that if the magnetic flow of a pair $(g,\\Omega)$ is $C^1$-conjugate to the horocycle flow of a hyperbolic metric $\\bar{g}$ then there exists a constant $a>0$, such that $ag$ and $\\bar{g}$ are isometric and $a^{-1}\\Omega$ is, up to a sign, the area form of $g$. The characterization also implies that if a magnetic flow is Ma\\~n\\'e critical and uniquely ergodic it must be the horocycle flow. As a by-product we also obtain results on existence of closed magnetic geodesics for almost all energy levels in the case weakly exact magnetic fields on arbitrary manifolds.", "revisions": [ { "version": "v1", "updated": "2004-09-27T16:55:43.000Z" } ], "analyses": { "keywords": [ "magnetic rigidity", "magnetic flow", "zero asymptotic maslov index", "case weakly exact magnetic fields", "area form" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math......9528P" } } }