{ "id": "1112.5888", "version": "v1", "published": "2011-12-26T19:51:34.000Z", "updated": "2011-12-26T19:51:34.000Z", "title": "On smooth extensions of vector-valued functions defined on closed subsets of Banach spaces", "authors": [ "M. Jimenez-Sevilla", "L. Sanchez-Gonzalez" ], "comment": "17 pages", "categories": [ "math.FA" ], "abstract": "Let $X$ and $Z$ be Banach spaces, $A$ a closed subset of $X$ and a mapping $f:A \\to Z$. We give necessary and sufficient conditions to obtain a $C^1$ smooth mapping $F:X \\to Z$ such that $F_{\\mid_A}=f$, when either (i) $X$ and $Z$ are Hilbert spaces and $X$ is separable, or (ii) $X^*$ is separable and $Z$ is an absolute Lipschitz retract, or (iii) $X=L_2$ and $Z=L_p$ with $1