{ "id": "2408.16348", "version": "v1", "published": "2024-08-29T08:35:42.000Z", "updated": "2024-08-29T08:35:42.000Z", "title": "Improved well-posedness for quasilinear and sharp local well-posedness for semilinear KP-I equations", "authors": [ "Shinya Kinoshita", "Akansha Sanwal", "Robert Schippa" ], "comment": "72 pages", "categories": [ "math.AP" ], "abstract": "We show new well-posedness results in anisotropic Sobolev spaces for dispersion-generalized KP-I equations with increased dispersion compared to the KP-I equation. We obtain the sharp dispersion rate, below which generalized KP-I equations on $\\mathbb{R}^2$ and on $\\mathbb{R} \\times \\mathbb{T}$ exhibit quasilinear behavior. In the quasilinear regime, we show improved well-posedness results relying on short-time Fourier restriction. In the semilinear regime, we show sharp well-posedness with analytic data-to-solution mapping. On $\\mathbb{R}^2$ we cover the full subcritical range, whereas on $\\mathbb{R} \\times \\mathbb{T}$ the sharp well-posedness is strictly subcritical. Nonlinear Loomis-Whitney inequalities are one ingredient. These are presently proved for Borel measures with growth condition reflecting the different geometries of the plane $\\mathbb{R}^2$, the cylinder $\\mathbb{R} \\times \\mathbb{T}$, and the torus $\\mathbb{T}^2$. Finally, we point out that on tori $\\mathbb{T}^2_\\gamma$, KP-I equations are never semilinear.", "revisions": [ { "version": "v1", "updated": "2024-08-29T08:35:42.000Z" } ], "analyses": { "keywords": [ "sharp local well-posedness", "semilinear kp-i equations", "well-posedness results", "sharp well-posedness", "nonlinear loomis-whitney inequalities" ], "note": { "typesetting": "TeX", "pages": 72, "language": "en", "license": "arXiv", "status": "editable" } } }