{ "id": "1904.04722", "version": "v1", "published": "2019-04-09T15:03:35.000Z", "updated": "2019-04-09T15:03:35.000Z", "title": "Regularity theory and Green's function for elliptic equations with lower order terms in unbounded domains", "authors": [ "Mihalis Mourgoglou" ], "categories": [ "math.AP" ], "abstract": "We consider elliptic operators in divergence form with lower order terms of the form $Lu = -\\text{div} (A \\cdot \\nabla u + b u ) - c\\cdot \\nabla u - du$, in an open set $\\Omega \\subset \\mathbb{R}^n$, $n \\geq 3$, with possibly infinite Lebesgue measure. We assume that the $n \\times n$ matrix $A$ is uniformly elliptic with real, merely bounded and possibly non-symmetric coefficients, $b, c \\in L^n(\\Omega)$, $d \\in L^\\frac{n}{2}(\\Omega)$, and $ \\mathcal{K}_{Dini,1/2}(\\Omega)$ stands for a variant of the Stummel-Kato class with a Dini-type condition. If $\\text{div} b +d \\leq 0$ holds, or if $-\\text{div} c + d \\leq 0$ and $|b+c|^2 \\in \\mathcal{K}_{Dini,1/2}(\\Omega)$ hold, then we develop a De Giorgi/Nash/Moser theory for solutions of $Lu = f - \\text{div} g$, where $ f$ and $|g|^2 \\in \\mathcal{K}_{Dini,1/2}(\\Omega)$. The most important feature of our proofs is that all the estimates are scale invariant and independent of $\\Omega$. We also show that the variational Dirichlet problem is well-posed and, for its solution, we prove a Wiener-type criterion for boundary regularity. Finally, assuming that $|b+c|^2 \\in \\mathcal{K}_{Dini,1/2}(\\Omega)$, we construct Green's functions associated with operators of the form above and show, among others, global pointwise bounds.", "revisions": [ { "version": "v1", "updated": "2019-04-09T15:03:35.000Z" } ], "analyses": { "subjects": [ "35A08", "35B50", "35B51", "35B65", "35J08", "35J15", "35J20", "35J25", "35J67", "35J86" ], "keywords": [ "lower order terms", "regularity theory", "elliptic equations", "unbounded domains", "construct greens functions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }