{ "id": "2101.08586", "version": "v1", "published": "2021-01-21T12:58:58.000Z", "updated": "2021-01-21T12:58:58.000Z", "title": "Improved quantitative regularity for the Navier-Stokes equations in a scale of critical spaces", "authors": [ "Stan Palasek" ], "comment": "48 pages, 1 figure", "categories": [ "math.AP" ], "abstract": "We prove a quantitative regularity theorem and blowup criterion for classical solutions of the three-dimensional Navier-Stokes equations satisfying certain critical conditions. The solutions we consider have $\\|r^{1-\\frac3q}u\\|_{L_t^\\infty L_x^q}<\\infty$ where $r=\\sqrt{x_1^2+x_2^2}$ and either $q\\in(3,\\infty)$, or $u$ is axisymmetric and $q\\in(2,3]$. Using the strategy of Tao (2019), we obtain improved subcritical estimates for such solutions depending only on the double exponential of the critical norm. One consequence is a double logarithmic lower bound on the blowup rate. We use some new tools such as a decomposition of the solution that allows us to use energy methods in these spaces, as well as a Carleman inequality for the heat equation suited for proving quantitative backward uniqueness in cylindrical regions.", "revisions": [ { "version": "v1", "updated": "2021-01-21T12:58:58.000Z" } ], "analyses": { "subjects": [ "35Q35", "76D05" ], "keywords": [ "critical spaces", "double logarithmic lower bound", "three-dimensional navier-stokes equations satisfying", "blowup rate", "quantitative regularity theorem" ], "note": { "typesetting": "TeX", "pages": 48, "language": "en", "license": "arXiv", "status": "editable" } } }