{ "id": "math/0501172", "version": "v1", "published": "2005-01-11T21:01:33.000Z", "updated": "2005-01-11T21:01:33.000Z", "title": "Longitudinal KAM-cocycles and action spectra of magnetic flows", "authors": [ "Nurlan S. Dairbekov Gabriel P. Paternain" ], "categories": [ "math.DS", "math.DG" ], "abstract": "Let $M$ be a closed oriented surface and let $\\Omega$ be a non-exact 2-form. Suppose that the magnetic flow $\\phi$ of the pair $(g,\\Omega)$ is Anosov. We show that the longitudinal KAM-cocycle of $\\phi$ is a coboundary if and only the Gaussian curvature is constant and $\\Omega$ is a constant multiple of the area form thus extending the results in \\cite{P2}. We also show infinitesimal rigidity of the action spectrum of $\\phi$ with respect to variations of $\\Omega$. Both results are obtained by showing that if $G:M\\to\\mathbb R$ is any smooth function and $\\omega$ is any smooth 1-form on $M$ such that $G(x)+\\omega_{x}(v)$ integrates to zero along any closed orbit of $\\phi$, then $G$ must be identically zero and $\\omega$ must be exact.", "revisions": [ { "version": "v1", "updated": "2005-01-11T21:01:33.000Z" } ], "analyses": { "keywords": [ "magnetic flow", "longitudinal kam-cocycle", "action spectrum", "constant multiple", "area form" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2005math......1172P" } } }