{ "id": "2109.09387", "version": "v1", "published": "2021-09-20T09:20:58.000Z", "updated": "2021-09-20T09:20:58.000Z", "title": "Amplitude equations for SPDEs driven by fractional additive noise with small Hurst parameter", "authors": [ "Dirk Blömker", "Alexandra Neamtu" ], "comment": "Preprint, 32 pages", "categories": [ "math.PR", "math.DS" ], "abstract": "We study stochastic partial differential equations (SPDEs) with potentially very rough fractional noise with Hurst parameter $H\\in(0,1)$. Close to a change of stability measured with a small parameter $\\varepsilon$, we rely on the natural separation of time-scales and establish a simplified description of the essential dynamics. We prove that up to an error term bounded by a power of $\\varepsilon$ depending on the Hurst parameter we can approximate the solution of the SPDE in first order by an SDE, the so called amplitude equation, and in second order by a fast infinite dimensional Ornstein-Uhlenbeck process. To this aim we need to establish an explicit averaging result for stochastic integrals driven by rough fractional noise for small Hurst parameters.", "revisions": [ { "version": "v1", "updated": "2021-09-20T09:20:58.000Z" } ], "analyses": { "subjects": [ "60H15", "60G22", "37H20" ], "keywords": [ "small hurst parameter", "fractional additive noise", "amplitude equation", "infinite dimensional ornstein-uhlenbeck process", "spdes driven" ], "note": { "typesetting": "TeX", "pages": 32, "language": "en", "license": "arXiv", "status": "editable" } } }