{ "id": "1709.04713", "version": "v1", "published": "2017-09-14T11:34:29.000Z", "updated": "2017-09-14T11:34:29.000Z", "title": "Classical well-posedness in dispersive equations with nonlinearities of mild regularity, and a composition theorem in Besov spaces", "authors": [ "Mats Ehrnström", "Long Pei" ], "categories": [ "math.AP" ], "abstract": "For both localized and periodic initial data, we prove local existence in classical energy space $H^s, s>\\frac{3}{2}$, for a class of dispersive equations $u_{t}+(n(u))_{x}+Lu_{x}=0$ with nonlinearities of mild regularity. Our results are valid for symmetric Fourier multiplier operators $L$ whose symbol is of temperate growth, and $n(\\cdot)$ in local Sobolev space $H^{s+2}_{\\mathrm{loc}}(\\mathbb{R})$. In particular, the results include non-smooth and exponentially growing nonlinearities. Our proof is based on a combination of semi-group methods and a new composition result for Besov spaces. In particular, we extend a previous result for Nemytskii operators on Besov spaces on $\\mathbb{R}$ to the periodic setting by using the difference-derivative characterization of Besov spaces.", "revisions": [ { "version": "v1", "updated": "2017-09-14T11:34:29.000Z" } ], "analyses": { "subjects": [ "47J35", "35Q53", "45J05", "76B15" ], "keywords": [ "besov spaces", "mild regularity", "dispersive equations", "composition theorem", "classical well-posedness" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }