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Related papers: Mixing for Time-Changes of Heisenberg Nilflows

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We consider smooth flows preserving a smooth invariant measure, or, equivalently, locally Hamiltonian flows on compact orientable surfaces and show that almost every such locally Hamiltonian flow with only simple saddles has singular…

Dynamical Systems · Mathematics 2025-05-20 Krzysztof Frączek , Adam Kanigowski , Corinna Ulcigrai

It is proved that all special flows over the rotation by an irrational $\alpha$ with bounded partial quotients and under $f$ which is piecewise absolutely continuous with a non-zero sum of jumps are mildly mixing. Such flows are also shown…

Dynamical Systems · Mathematics 2007-05-23 Krzysztof Fraczek , Mariusz Lemanczyk

For any accessible partially hyperbolic homogeneous flow, we show that all smooth time changes are K and hence mixing of all orders. We also establish stable ergodicity for time-one map of these time changes.

Dynamical Systems · Mathematics 2020-10-09 Changguang Dong

We consider smooth time-changes of the classical horocycle flows on the unit tangent bundle of a compact hyperbolic surface and prove sharp bounds on the rate of equidistribution and the rate of mixing. We then derive results on the…

Dynamical Systems · Mathematics 2012-02-24 Giovanni Forni , Corinna Ulcigrai

Let $T=(T_t^f)_{t\in \mathbb{R}}$ be a special flow built over an IET $T : T \to T$ of bounded type, under a roof function f with symmetric logarithmic singularities at a subset of discontinuities of T. We show that $T$ satisfies so-called…

Dynamical Systems · Mathematics 2014-09-11 Adam Kanigowski , Joanna Kułaga Przymus

Considering a Markov chain defined on a cycle, near-quadratic improvement of mixing is shown when only a subtle perturbation is introduced to the structure and non-reversible transition probabilities are used. More precisely, a mixing time…

Probability · Mathematics 2024-11-12 Shi Feng , Balázs Gerencsér

We consider special flows over two-dimensional rotations by $(\alpha,\beta)$ on $\T^2$ and under piecewise $C^2$ roof functions $f$ satisfying von Neumann's condition $\int_{\T^2}f_x(x,y)\,dx\,dy\neq 0\neq \int_{\T^2}f_y(x,y)\,dx\,dy.$ Such…

Dynamical Systems · Mathematics 2010-12-16 K. Fraczek , M. Lemanczyk

Normalizing flows are a promising tool for modeling probability distributions in physical systems. While state-of-the-art flows accurately approximate distributions and energies, applications in physics additionally require smooth energies…

Machine Learning · Statistics 2021-12-01 Jonas Köhler , Andreas Krämer , Frank Noé

We obtain optimal moment bounds for Birkhoff sums, and optimal concentration inequalities, for a large class of slowly mixing dynamical systems, including those that admit anomalous diffusion in the form of a stable law or a central limit…

Dynamical Systems · Mathematics 2017-09-01 Sébastien Gouëzel , Ian Melbourne

For nonlinear hyperbolic systems of conservation laws in one space variable, we establish the existence of nonclassical entropy solutions exhibiting nonlinear interactions between shock waves with strong strength. The proposed theory is…

Analysis of PDEs · Mathematics 2021-05-17 Eva Kardhashi , Marc Laforest , Philippe G. LeFloch

We show that ergodic flows in noncommutative fully symmetric spaces (associated with a semifinite von Neumann algebra) generated by continuous semigroups of positive Dunford-Schwartz operators and modulated by bounded Besicovitch almost…

Operator Algebras · Mathematics 2018-09-07 Vladimir Chilin , Semyon Litvinov

We study the averaging method for flows perturbed by a dynamical system preserving an infinite measure. Motivated by the case of perturbation by the collision dynamic on the finite horizon $\mathbb Z$-periodic Lorentz gas and in view of…

Dynamical Systems · Mathematics 2024-01-23 Maxence Phalempin

This work is a contribution to the study of the ergodic and stochastic properties of Z^d-periodic dynamical systems preserving an infinite measure. We establish functional limit theorems for natural Birkhoff sums related to local times of…

Dynamical Systems · Mathematics 2023-12-06 Françoise Pène

By definition, a map quasiperiodic on a set $X$ if the map is conjugate to a pure rotation. Suppose we have a trajectory $(x_n)$ that we suspect is quasiperiodic. How do we determine if it is? In this paper we show how to compute the…

Dynamical Systems · Mathematics 2018-01-31 Suddhasattwa Das , James A. Yorke

For an ergodic flow, a range of rates of convergence of Birkhoff averages from the maximum rate to an arbitrarily slow rate is realized by choosing the averaging function. For torus windings, the continuity of the averaging functions is…

Dynamical Systems · Mathematics 2026-01-30 I. V. Podvigin , V. V. Ryzhikov

We prove that minimal area-preserving flows locally given by a smooth Hamiltonian on a closed surface of any genus are typically (in the measure-theoretical sense) not mixing. The result is obtained by considering special flows over…

Dynamical Systems · Mathematics 2009-01-30 Corinna Ulcigrai

We study time-changes of unipotent flows on finite volume quotients of semisimple linear groups, generalising previous work by Ratner on time-changes of horocycle flows. Any measurable isomorphism between time-changes of unipotent flows…

Dynamical Systems · Mathematics 2024-07-22 Mauro Artigiani , Livio Flaminio , Davide Ravotti

We study enhancement of diffusive mixing by fast incompressible time-periodic flows. The class of relaxation-enhancing flows that are especially efficient in speeding up mixing has been introduced in [2]. The relaxation-enhancing property…

Analysis of PDEs · Mathematics 2007-07-02 Alexander Kiselev , Roman Shterenberg , Andrej Zlatos

Normalizing flows are objects used for modeling complicated probability density functions, and have attracted considerable interest in recent years. Many flexible families of normalizing flows have been developed. However, the focus to date…

Methodology · Statistics 2023-01-18 Tin Lok James Ng , Andrew Zammit-Mangion

Mixing of materials is fundamental to many natural phenomena and engineering applications. The presence of discontinuous deformations - such as shear banding or wall slip - creates new mechanisms for mixing and transport beyond those…

Chaotic Dynamics · Physics 2016-02-18 Lachlan D. Smith , Murray Rudman , Daniel R. Lester , Guy Metcalfe