{ "id": "2305.05961", "version": "v1", "published": "2023-05-10T08:11:08.000Z", "updated": "2023-05-10T08:11:08.000Z", "title": "Regularizing properties of n-Laplace systems with antisymmetric potentials in Lorentz spaces", "authors": [ "Dorian Martino", "Armin Schikorra" ], "categories": [ "math.AP" ], "abstract": "We show continuity of solutions $u \\in W^{1,n}(B^n,\\mathbb{R}^N)$ to the system \\[ -{\\rm div} (|\\nabla u|^{n-2} \\nabla u) = \\Omega \\cdot |\\nabla u|^{n-2} \\nabla u \\] when $\\Omega$ is an $L^n$-antisymmetric potential -- and additionally satisfies a Lorentz-space assumption. To obtain our result we study a rotated n-Laplace system \\[ -{\\rm div} (Q|\\nabla u|^{n-2} \\nabla u) = \\tilde{\\Omega} \\cdot |\\nabla u|^{n-2} \\nabla u, \\] where $Q \\in W^{1,n}(B^n,SO(N))$ is the Coulomb gauge which ensures improved Lorentz-space integrability of $\\tilde{\\Omega}$. Because of the matrix-term $Q$, this system does not fall directly into Kuusi-Mingione's vectorial potential theory. However, we adapt ideas of their theory together with Iwaniec' stability result to obtain $L^{(n,\\infty)}$-estimates of the gradient of a solution which, by an iteration argument leads to the regularity of solutions. As a corollary of our argument we see that $n$-harmonic maps into manifolds are continuous if their gradient belongs to the Lorentz-space $L^{(n,2)}$ -- which is a trivial and optimal assumption if $n=2$, and the weakest assumption to date for the regularity of critical $n$-harmonic maps, without any added differentiability assumption.", "revisions": [ { "version": "v1", "updated": "2023-05-10T08:11:08.000Z" } ], "analyses": { "keywords": [ "antisymmetric potential", "lorentz spaces", "regularizing properties", "harmonic maps", "kuusi-mingiones vectorial potential theory" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }