{ "id": "math/0203188", "version": "v1", "published": "2002-03-19T11:16:42.000Z", "updated": "2002-03-19T11:16:42.000Z", "title": "Optimal stability and instability results for a class of nearly integrable Hamiltonian systems", "authors": [ "Massimiliano Berti", "Luca Biasco", "Philippe Bolle" ], "comment": "6 pages", "categories": [ "math.DS", "math.FA" ], "abstract": "We consider a nearly integrable, non-isochronous, a-priori unstable Hamiltonian system with a (trigonometric polynomial) $O(\\mu)$-perturbation which does not preserve the unperturbed tori. We prove the existence of Arnold diffusion with diffusion time $T_d = O((1/ \\mu) \\log (1/ \\mu))$ by a variational method which does not require the existence of ``transition chains of tori'' provided by KAM theory. We also prove that our estimate of the diffusion time $T_d$ is optimal as a consequence of a general stability result proved via classical perturbation theory.", "revisions": [ { "version": "v1", "updated": "2002-03-19T11:16:42.000Z" } ], "analyses": { "subjects": [ "37J40", "37J45" ], "keywords": [ "integrable hamiltonian systems", "optimal stability", "instability results", "diffusion time", "a-priori unstable hamiltonian system" ], "note": { "typesetting": "TeX", "pages": 6, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2002math......3188B" } } }