{ "id": "1008.4396", "version": "v4", "published": "2010-08-25T21:49:54.000Z", "updated": "2011-09-25T14:36:44.000Z", "title": "Non-concentration of quasimodes for integrable systems", "authors": [ "Jared Wunsch" ], "comment": "One addition to acknowledgments; to appear in Comm. PDE", "categories": [ "math.AP", "math-ph", "math.MP", "math.SP" ], "abstract": "We consider the possible concentration in phase space of a sequence of eigenfunctions (or, more generally, a quasimode) of an operator whose principal symbol has completely integrable Hamilton flow. The semiclassical wavefront set $WF_h$ of such a sequence is invariant under the Hamilton flow. In principle this may allow concentration of $WF_h$ along positive codimension sub-tori of a Liouville torus $\\mathcal{L}$ if there exist rational relations among the frequencies of the flow on $\\mathcal{L}.$ We show that, subject to non-degeneracy hypotheses, this concentration may not in fact occur. The main tools are the spreading of Lagrangian regularity on $\\mathcal{L}$ previously shown by Vasy and the author, and an analysis of higher order transport equations satisfied by the principal symbol of a Lagrangian quasimode.", "revisions": [ { "version": "v4", "updated": "2011-09-25T14:36:44.000Z" } ], "analyses": { "keywords": [ "integrable systems", "hamilton flow", "principal symbol", "non-concentration", "higher order transport equations" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1008.4396W" } } }