Characterizing finite sets of nonwandering points

Abstract

We characterize finite sets $S$ of nonwandering points for generic diffeomorphisms $f$ as those which are {\em uniformly bounded}, i.e., there is an uniform bound for small perturbations of the derivative of $f$ along the points in $S$ up to suitable iterates. We use this result to give a $C^1$ generic characterization of the Morse-Smale diffeomorphisms related to the weak Palis conjecture \cite{c}. Furthermore, we obtain another proof of the result by Liao and Pliss about the finiteness of sinks and sources for star diffeomorphisms \cite{l}, \cite{Pl}.