{ "id": "1904.08856", "version": "v1", "published": "2019-04-18T15:56:45.000Z", "updated": "2019-04-18T15:56:45.000Z", "title": "Geometric regularity for elliptic equations in double-divergence form", "authors": [ "Raimundo Leitão", "Edgard A. Pimentel", "Makson S. Santos" ], "categories": [ "math.AP" ], "abstract": "In this paper, we examine the regularity of the solutions to the double-divergence equation. We establish improved H\\\"older continuity as solutions approach their zero level-sets. In fact, we prove that $\\alpha$-H\\\"older continuous coefficients lead to solutions of class $\\mathcal{C}^{1^-}$, locally. Under the assumption of Sobolev differentiable coefficients, we establish regularity in the class $\\mathcal{C}^{1,1^-}$. Our results unveil improved continuity along a nonphysical free boundary, where the weak formulation of the problem vanishes. We argue through a geometric set of techniques, implemented by approximation methods. Such methods connect our problem of interest with a target profile. An iteration procedure imports information from this limiting configuration to the solutions of the double-divergence equation.", "revisions": [ { "version": "v1", "updated": "2019-04-18T15:56:45.000Z" } ], "analyses": { "subjects": [ "35B65", "35J15" ], "keywords": [ "elliptic equations", "double-divergence form", "geometric regularity", "double-divergence equation", "iteration procedure imports information" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }