This work provides rates of convergence in the Darling-Kac law for infinite measure preserving Pomeau-Manneville (unit interval) maps. Along the way we obtain error rates for the stable law associated with the first return map and the first return time to some suitable set inside the unit interval.

Nous étudions un exemple de transformation non uniformément hyperbolique de l’intervalle $[0,1[$. Des exemples analogues ont été étudiés par de nombreux auteurs. Notre méthode utilise une théorie spectrale, pour une classe d’opérateurs vérifiant des conditions faibles de Doeblin-Fortet, introduite dans [1]. Elle nous permet, en particulier, de donner une estimation de la vitesse de décroissance des corrélations pour des fonctions non höldériennes.

We construct ${}^{\infty }$ maps T on the interval and on the circle which are Lebesgue exact preserving an absolutely continuous infinite measure μ ≪ λ, such that for any probability measure ν ≪ λ the sequence ${\left(n^{-1}{\sum }_{k=0}^{n-1}\nu \circ T^{-k}\right)}_{n\ge 1}$ of arithmetical averages of image measures does not converge weakly.

The example is constructed of the C1-smooth skew product of interval maps possessing the one-dimensional ramified continuum (containing no arcs homeomorphic to the circle) with an infinite set of ramification points as the global attractor.

We prove that for every ϵ > 0 there exists a minimal diffeomorphism f: ² → ² of class $C^{3-ϵ}$ and semiconjugate to an ergodic translation with the following properties: zero entropy, sensitivity to initial conditions, and Li-Yorke chaos. These examples are obtained through the holonomy of the unstable foliation of Mañé’s example of a derived-from-Anosov diffeomorphism on ³.

Le Calvez a montré que si $F$ est un homéomorphisme isotope à l’identité d’une surface $M$ admettant un relèvement $\tilde{F}$ au revêtement universel n’ayant pas de points fixes, alors il existe un feuilletage topologique de $M$ transverse à la dynamique. Nous montrons que ce résultat se généralise au cas où $\tilde{F}$ admet des points fixes. Nous obtenons alors un feuilletage topologique singulier transverse à la dynamique dont les singularités sont un ensemble fermé de points fixes de $F$.

A (quadratic) Hubbard tree is an invariant tree connecting the critical orbit within the Julia set of a postcritically finite (quadratic) polynomial. It is easy to read off the kneading sequences from a quadratic Hubbard tree; the result in this paper handles the converse direction. Not every sequence on two symbols is realized as the kneading sequence of a real or complex quadratic polynomial. Milnor and Thurston classified all real-admissible sequences, and we give a classification of all complex-admissible...

We prove that for each integer $k\ge 2$ there is an open neighborhood ${𝒱}_k$ of the identity map of the 2-sphere $S^2$, in $C^1$ topology such that: if $G$ is a nilpotent subgroup of ${\mathrm{Diff}}^1\left(S^2\right)$ with length $k$ of nilpotency, generated by elements in ${𝒱}_k$, then the natural $G$-action on $S^2$ has nonempty fixed point set. Moreover, the $G$-action has at least two fixed points if the action has a finite nontrivial orbit.

We describe necessary and sufficient conditions for a fixed point free planar homeomorphism that preserves the standard Reeb foliation to embed in a planar flow that leaves the foliation invariant.

We consider a fixed point free homeomorphism $h$ of the closed band $B=ℝ\times [0,1]$ which leaves each leaf of a Reeb foliation on $B$ invariant. Assuming $h$ is the time one of various topological flows, we compare the restriction of the flows on the boundary.

Let $T_a$ be the tent map with slope a. Let c be its turning point, and ${\mu }_a$ the absolutely continuous invariant probability measure. For an arbitrary, bounded, almost everywhere continuous function g, it is shown that for almost every a, $ʃgd{\mu }_a=li{m}_{n\to \infty }\frac{1}{n}{\sum }_{i=0}^{n-1}g\left(T_a^i\left(c\right)\right)$. As a corollary, we deduce that the critical point of a quadratic map is generically not typical for its absolutely continuous invariant probability measure, if it exists.