{ "id": "0705.2216", "version": "v3", "published": "2007-05-15T19:44:31.000Z", "updated": "2008-04-01T07:18:32.000Z", "title": "Real interpolation of Sobolev spaces", "authors": [ "Nadine Badr" ], "comment": "30 pages", "categories": [ "math.FA", "math.MG" ], "abstract": "We prove that $W^{1}_{p}$ is an interpolation space between $W^{1}_{p_{1}}$ and $W^{1}_{p_{2}}$ for $p>q_{0}$ and $1\\leq p_{1}