{ "id": "1711.05543", "version": "v1", "published": "2017-11-15T12:47:46.000Z", "updated": "2017-11-15T12:47:46.000Z", "title": "Time-Changes of Heisenberg nilflows", "authors": [ "Giovanni Forni", "Adam Kanigowski" ], "categories": [ "math.DS" ], "abstract": "We consider the three dimensional Heisenberg nilflows. Under a full measure set Diophantine condition on the generator of the flow we construct Bufetov functionals which are asymptotic to ergodic integrals for sufficiently smooth functions, have a modular property and scale exactly under the renor- malization dynamics. We then prove analyticity of the functionals in the transverse directions to the flow. As a consequence of this analyticity property we derive that there exists a full measure set of nilflows such that generic (non-trivial) time-changes are mixing and moreover have a \"stretched polynomial\" decay of correlations for sufficiently smooth functions. Moreover we also prove that there exists a full Hausdorff dimension set of nilflows such that generic non-trivial time-changes have polynomial decay of correlations.", "revisions": [ { "version": "v1", "updated": "2017-11-15T12:47:46.000Z" } ], "analyses": { "keywords": [ "time-changes", "sufficiently smooth functions", "full measure set diophantine condition", "full hausdorff dimension set", "construct bufetov functionals" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }