{ "id": "1608.08408", "version": "v1", "published": "2016-08-30T11:42:35.000Z", "updated": "2016-08-30T11:42:35.000Z", "title": "Arnold diffusion for a complete family of perturbations", "authors": [ "Amadeu Delshams", "Rodrigo G. Schaefer" ], "categories": [ "math.DS" ], "abstract": "In this work we illustrate the Arnold diffusion in a concrete example---the \\emph{a priori} unstable Hamiltonian system of $2+1/2$ degrees of freedom $H(p,q,I,\\varphi,s) = p^{2}/2+\\cos q -1 +I^{2}/2 + h(q,\\varphi,s;\\varepsilon)$---proving that for \\emph{any} small periodic perturbation of the form $h(q,\\varphi,s;\\varepsilon) = \\varepsilon\\cos q\\left( a_{00} + a_{10}\\cos\\varphi + a_{01}\\cos s \\right)$ ($a_{10}a_{01} \\neq 0$) there is global instability for the action. For the proof we apply a geometrical mechanism based in the so-called Scattering map. This work has the following structure: In a first stage, for a more restricted case ($I^*\\thicksim\\pi/2\\mu$, $\\mu = a_{10}/a_{01}$), we use only one scattering map, with a special property: the existence of simple paths of diffusion called highways. Later, in the general case we combine a scattering map with the inner map (inner dynamics) to prove the more general result (the existence of the instability for any $\\mu$). The bifurcations of the scattering map are also studied as a function of $\\mu$. Finally, we give an estimate for the time of diffusion, and we show that this time is primarily the time spent under the scattering map.", "revisions": [ { "version": "v1", "updated": "2016-08-30T11:42:35.000Z" } ], "analyses": { "subjects": [ "37J40" ], "keywords": [ "arnold diffusion", "scattering map", "complete family", "small periodic perturbation", "special property" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }