{ "id": "2411.09930", "version": "v1", "published": "2024-11-15T04:13:50.000Z", "updated": "2024-11-15T04:13:50.000Z", "title": "On some regularity properties of mixed local and nonlocal elliptic equations", "authors": [ "Xifeng Su", "Enrico Valdinoci", "Yuanhong Wei", "Jiwen Zhang" ], "comment": "Journal of Differential Equations", "categories": [ "math.AP" ], "abstract": "This article is concerned with ``up to $C^{2, \\alpha}$-regularity results'' about a mixed local-nonlocal nonlinear elliptic equation which is driven by the superposition of Laplacian and fractional Laplacian operators. First of all, an estimate on the $L^\\infty$ norm of weak solutions is established for more general cases than the ones present in the literature, including here critical nonlinearities. We then prove the interior $C^{1,\\alpha}$-regularity and the $C^{1,\\alpha}$-regularity up to the boundary of weak solutions, which extends previous results by the authors [X. Su, E. Valdinoci, Y. Wei and J. Zhang, Math. Z. (2022)], where the nonlinearities considered were of subcritical type. In addition, we establish the interior $C^{2,\\alpha}$-regularity of solutions for all $s\\in(0,1)$ and the $C^{2,\\alpha}$-regularity up to the boundary for all $s\\in(0,\\frac{1}{2})$, with sharp regularity exponents. For further perusal, we also include a strong maximum principle and some properties about the principal eigenvalue.", "revisions": [ { "version": "v1", "updated": "2024-11-15T04:13:50.000Z" } ], "analyses": { "subjects": [ "35B65", "35R11", "35J67" ], "keywords": [ "nonlocal elliptic equations", "regularity properties", "mixed local-nonlocal nonlinear elliptic equation", "weak solutions", "fractional laplacian operators" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }