Source Themes

Existence of measures of maximal entropy for $C^r$ interval maps

We show that a $ \mathcal {C}^{r}$ $ (r1)$ map of the interval $ f:[0,1]\rightarrow [0,1]$ with topological entropy larger than $ \frac {\log \Vert f'\Vert _{\infty }}{r}$ admits at least one measure of maximal entropy. Moreover the number of …

Symbolic extensions for partially hyperbolic dynamical systems with 2-dimensional center bundle.

We relate the symbolic extension entropy of a partially hyperbolic dynamical system to the entropy appearing at small scales in local center manifolds. In particular, we prove the existence of symbolic extensions for $C^2$ partially hyperbolic …

Symbolic extensions in intermediate smoothness on surfaces

We prove that $C^r$ maps with $r 1$ on a compact surface have symbolic extensions, i.e. topological extensions which are subshifts over a finite alphabet. More precisely we give a sharp upper bound on the so-called symbolic extension entropy, which …

Quantitative Morse Sard theorem via algebraic lemma.

We give a short proof of the so-called Quantitative Morse-Sard Theorem as an application of Gromov?s Algebraic Lemma.

Symbolic extensions and continuity properties of the entropy

Examples of $C^r$ interval map with large symbolic extension entropy. .

For any integer $r\geq2$ and any real $\epsilon0$, we construct an explicit example of $\mathcal{C}^r$ interval map $f$ with maximal symbolic extension entropy. Similar examples had been already built by T.Downarowicz and S.Newhouse for …

$C^2$ surface diffeomorphisms have symbolic extensions

We prove that \(\mathcal{C}^{2}\) surface diffeomorphisms have symbolic extensions, i.e. topological extensions which are subshifts over a finite alphabet. Following the strategy of Downarowicz and Maass we bound the local entropy of ergodic measures …

Orders of accumulation of entropy

For a continuous map $T$ of a compact metrizable space $X$ with finite topological entropy, the order of accumulation of entropy of $T$ is a countable ordinal that arises in the context of entropy structures and symbolic extensions. We show that …

Symbolic extensions for nonuniformly entropy expanding maps

A direct proof of the tail variational principle and its extension to maps