v2
https://www.raco.cat/index.php/CollectaneaMathematica/article/view/56316
2014-03-14T10:41:08Z
Collectanea Mathematica
1995: Vol.: 46 Núm.: 3; 289-301
$C$-nearest points and the drop property
Maâden, Abdelhakim
1995-01-12 00:00:00
url:https://www.raco.cat/index.php/CollectaneaMathematica/article/view/56316
eng
For a closed convex set $C$ with non-empty interior, we define the $C$-nearest distance from $x$ to a closed set $F$. We show that, if there exists in the Banach space $X$ a closed convex set with non-empty interior satisfying the drop property, then for all closed subset $F$ of $X$, there exists a dense $G_\delta$ subset $\Gamma$ of $X\setminus \{x; \rho(F, x) = 0\}$ such that every $x\in\Gamma$ has a $C$-nearest point in $F$. We also prove that every smooth (unbounded) convex set with the drop property has the smooth drop property.