{ "id": "1110.5189", "version": "v1", "published": "2011-10-24T10:34:58.000Z", "updated": "2011-10-24T10:34:58.000Z", "title": "The regularity problem for elliptic operators with boundary data in Hardy-Sobolev space $HS^1$", "authors": [ "Martin Dindoš", "Josef Kirsch" ], "comment": "20 pages", "categories": [ "math.AP" ], "abstract": "Let $\\Omega$ be a Lipschitz domain in $\\mathbb R^n,n\\geq 3,$ and $L=\\divt A\\nabla$ be a second order elliptic operator in divergence form. We will establish that the solvability of the Dirichlet regularity problem for boundary data in Hardy-Sobolev space $\\HS$ is equivalent to the solvability of the Dirichlet regularity problem for boundary data in $H^{1,p}$ for some $1