Poisson approximation for the number of visits to balls in nonuniformly hyperbolic dynamical systems

Poisson law for some nonuniformly hyperbolic dynamical systems with polynomial rate of mixing

We consider some nonuniformly hyperbolic invertible dynamical systems which are modeled by a Gibbs-Markov-Young tower. We assume a polynomial tail for the inducing time and a polynomial control of hyperbolicity, as introduced by Alves, Pinheiro and Azevedo. These systems admit a physical measure with polynomial rate of mixing. In this paper we prove that the distribution of the number of visits to a ball B(x, r) converges to a Poisson distribution as the radius r $\to$ 0 and after suitable normalization.

非一致双曲映射的几乎必然不变原理中的速率

Rates in almost sure invariance principle for nonuniformly hyperbolic maps

本文在不假设稳定叶指数压缩的条件下，为非一致双曲映射证明了误差速率接近最优的几乎必然不变原理，并利用双侧更新 Markov 转移的半共轭方法，首次覆盖了 Bunimovich flowers 等缓慢混合系统。

A conditional proof of the non-contraction property for N falling balls

Wojtkowski's system of $N$, $N \geq 2$, falling balls is a nonuniformly hyperbolic smooth dynamical system with singularities. It is still an open question whether this system is ergodic. We contribute towards an affirmative answer, by proving the non-contraction property, conditioned by the assumption of strict unboundedness. For a certain mass ratio the configuration space can be unfolded to a billiard table where the daunting proper alignment condition is satisfied. We prove, that the aforementioned unfolded system with three degrees of freedom is ergodic.

Limiting distribution and error terms for the number of visits to balls in non-uniformly hyperbolic dynamical systems

We show that for systems that allow a Young tower construction with polynomially decaying correlations the return times to metric balls are in the limit Poisson distributed. We also provide error terms which are powers of logarithm of the radius. In order to get those uniform rates of convergence the balls centres have to avoid a set whose size is estimated to be of similar order. This result can be applied to non-uniformly hyperbolic maps and to any invariant measure that satisfies a weak regularity condition. In particular it shows that the return times to balls is Poissonian for SRB measure…

Number of visits in arbitrary sets for $ϕ$-mixing dynamics

It is well-known that, for sufficiently mixing dynamical systems, the number of visits to balls and cylinders of vanishing measure is approximately Poisson compound distributed in the Kac scaling. Here we extend this kind of results when the target set is an arbitrary set with vanishing measure in the case of $ϕ$-mixing systems. The error of approximation in total variation is derived using Stein-Chen method. An important part of the paper is dedicated to examples to illustrate the assumptions, as well as applications to temporal synchronisation of $g$-measures

加法机与开放动力系统

Adding machines and open dynamical systems

该研究针对紧度量空间上的开放动力系统，以加法机这一简单螺线管系统为对象，证明了当开球收缩时，生成首次访问开球无穷次变化的犹豫不决轨迹的点集为剩余集。