Preprint MA 53/2006

On some properties of interval maps with zero topological entropy

Zdeněk Kočan

We consider six properties of continuous maps from compact interval into itself: (i) $h(f)=0$; (ii) $\Rec (f)$ is $F_\sigma$; (iii) $f$ is Lyapunov stable on $\Per(f)$; (iv) for every simple system $(I_{n})_{n \in \N}$ of intervals associated with an infinite $\omega$-limit set, $\lim_{n\to\infty}\max_{0\leq i < 2^{n}} \lambda (f^{i} (I_{n})) = 0$; (v) $\Per (f)$ is $G_\delta$; (vi) every linearly ordered chain of $\omega$-limit sets is countable. They were believed to be equivalent. Recently some authors provide counterexamples showing that this is not the case. In this paper we give all the relations between these properties. We show that (iv) $\Rightarrow$ (iii) $\Rightarrow$ (ii) $\Rightarrow$ (i), (iv) $\Rightarrow$ (vi) $\Rightarrow$ (i), and (v) $\Rightarrow$ (i), and that there is no other implication between these properties.