Time-symmetric cycles.
Topological and measurable dynamics of Lorenz maps [Book]
Topological conjugacies of piecewise monotone interval maps.
Topological entropy and variation for transitive maps
Topological groups with Rokhlin properties
In his classical paper [Ann. of Math. 45 (1944)] P. R. Halmos shows that weak mixing is generic in the measure preserving transformations. Later, in his book, Lectures on Ergodic Theory, he gave a more streamlined proof of this fact based on a fundamental lemma due to V. A. Rokhlin. For this reason the name of Rokhlin has been attached to a variety of results, old and new, relating to the density of conjugacy classes in topological groups. In this paper we will survey some of the new developments...
Topological invariance of the Collet–Eckmann property for S-unimodal maps
We prove that if f, g are smooth unimodal maps of the interval with negative Schwarzian derivative, conjugated by a homeomorphism of the interval, and f is Collet-Eckmann, then so is g.
Topological sequence entropy for maps of the circle
A continuous map of the interval is chaotic iff there is an increasing sequence of nonnegative integers such that the topological sequence entropy of relative to , , is positive ([FS]). On the other hand, for any increasing sequence of nonnegative integers there is a chaotic map of the interval such that ([H]). We prove that the same results hold for maps of the circle. We also prove some preliminary results concerning topological sequence entropy for maps of general compact metric...
Topological transitivity and strong transitivity.
Trajectory of the turning point is dense for a co-σ-porous set of tent maps
It is known that for almost every (with respect to Lebesgue measure) a ∈ [√2,2] the forward trajectory of the turning point of the tent map with slope a is dense in the interval of transitivity of . We prove that the complement of this set of parameters of full measure is σ-porous.
Transfer operator for piecewise affine approximations of interval maps
Transitive sensitive subsystems for interval maps
We prove that for continuous interval maps the existence of a non-empty closed invariant subset which is transitive and sensitive to initial conditions is implied by positive topological entropy and implies chaos in the sense of Li-Yorke, and we exhibit examples showing that these three notions are distinct.
Travaux de D. Anosov et S. Smale sur les difféomorphismes
Triangular maps with the chain recurrent points periodic.
Twist systems on the interval
Let I be a compact real interval and let f:I → I be continuous. We describe an interval analogy of the irrational circle rotation that occurs as a subsystem of the dynamical system (I,f)-we call it an irrational twist system. Using a coding we show that any irrational twist system is strictly ergodic. We also prove that irrational twist systems exist as subsystems of a large class of systems (I,f) having a cycle of odd period greater than one.
Type-II internittency in a class of two coupled one-dimensional maps.
Uncountable ω-limit sets with isolated points
We give two examples of tent maps with uncountable (as it happens, post-critical) ω-limit sets, which have isolated points, with interesting structures. Such ω-limit sets must be of the form C ∪ R, where C is a Cantor set and R is a scattered set. Firstly, it is known that there is a restriction on the topological structure of countable ω-limit sets for finite-to-one maps satisfying at least some weak form of expansivity. We show that this restriction does not hold if the ω-limit set is uncountable....
Une version feuilletée équivariante du théorème de translation de Brouwer
The Brouwer’s plane translation theorem asserts that for a fixed point free orientation preserving homeomorphism f of the plane, every point belongs to a Brouwer line: a proper topological embedding C of R, disjoint from its image and separating f(C) and f–1(C). Suppose that f commutes with the elements of a discrete group G of orientation preserving homeomorphisms acting freely and properly on the plane. We will construct a G-invariant topological foliation of the plane by Brouwer lines. We apply...
Uniformly recurrent sequences and minimal Cantor omega-limit sets
We investigate the structure of kneading sequences that belong to unimodal maps for which the omega-limit set of the turning point is a minimal Cantor set. We define a scheme that can be used to generate uniformly recurrent and regularly recurrent infinite sequences over a finite alphabet. It is then shown that if the kneading sequence of a unimodal map can be generated from one of these schemes, then the omega-limit set of the turning point must be a minimal Cantor set.
Unimodal generalized pseudo-Anosov maps.
Unimodal time-symmetric dynamics.