{ "id": "2411.18452", "version": "v1", "published": "2024-11-27T15:42:50.000Z", "updated": "2024-11-27T15:42:50.000Z", "title": "Self-similar instability and forced nonuniqueness: an application to the 2D Euler equations", "authors": [ "Michele Dolce", "Giulia Mescolini" ], "comment": "20 pages", "categories": [ "math.AP" ], "abstract": "Building on an approach introduced by Golovkin in the '60s, we show that nonuniqueness in some forced PDEs is a direct consequence of the existence of a self-similar linearly unstable eigenvalue: the key point is a clever choice of the forcing term removing complicated nonlinear interactions. We use this method to give a short and self-contained proof of nonuniqueness in 2D perfect fluids, first obtained in Vishik's groundbreaking result. In particular, we present a direct construction of a forced self-similar unstable vortex, where we treat perturbatively the self-similar operator in a new and more quantitative way.", "revisions": [ { "version": "v1", "updated": "2024-11-27T15:42:50.000Z" } ], "analyses": { "subjects": [ "35Q31", "35Q35" ], "keywords": [ "2d euler equations", "self-similar instability", "forced nonuniqueness", "application", "term removing complicated nonlinear interactions" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable" } } }