English
Related papers

Related papers: Zero entropy is generic

200 papers

We prove that a topologically predictable action of a countable amenable group has zero topological entropy, as conjectured by Hochman. On route, we investigate invariant random orders and formulate a unified Kieffer-Pinsker formula for the…

Dynamical Systems · Mathematics 2019-02-06 Andrei Alpeev , Tom Meyerovitch , Sieye Ryu

This is the first part in a series in which sofic entropy theory is generalized to class-bijective extensions of sofic groupoids. Here we define topological and measure entropy and prove invariance. We also establish the variational…

Dynamical Systems · Mathematics 2013-03-19 Lewis Bowen

The relative entropy of the massive free bosonic field theory is studied on various compact Riemann surfaces as a universal quantity with physical significance, in particular, for gravitational phenomena. The exact expression for the sphere…

High Energy Physics - Theory · Physics 2008-11-26 Jose Gaite

Let $G$ be a countable discrete amenable group which acts continuously on a compact metric space $X$ and let $\mu$ be an ergodic $G-$invariant Borel probability measure on $X$. For a fixed tempered F{\o}lner sequence $\{F_n\}$ in $G$ with…

Dynamical Systems · Mathematics 2017-08-08 Dongmei Zheng , Ercai Chen

The notion of expansivity and its generalizations (measure expansive, measure positively expansive, continuum-wise expansive, countably-expansive) are well known for deterministic systems and can be a useful property for studying…

Dynamical Systems · Mathematics 2024-10-15 Rafael A. Bilbao , Marlon Oliveira , Eduardo Santana

This paper gives a free entropy theoretic perspective on amenable absorption results for free products of tracial von Neumann algebras. In particular, we give the first free entropy proof of Popa's famous result that the generator MASA in a…

Operator Algebras · Mathematics 2020-07-27 Ben Hayes , David Jekel , Brent Nelson , Thomas Sinclair

This article studies a structural aspect of measure-preserving actions of products of countable discrete groups, involving a so-called 'synergodic decomposition' in terms of the ergodic components of the actions of the two factor groups. We…

Dynamical Systems · Mathematics 2023-11-07 Peter Burton

We investigate the asymptotic structure of (possibly type III) crossed product von Neumann algebras $M = B \rtimes \Gamma$ arising from arbitrary actions $\Gamma \curvearrowright B$ of bi-exact discrete groups (e.g. free groups) on amenable…

Operator Algebras · Mathematics 2016-11-03 Cyril Houdayer , Yusuke Isono

We introduce infinitesimal weak containment for measure-preserving actions of a countable group $\Gamma$: an action $(X,\mu)$ is infinitesimally contained in $(Y,\nu)$ if the statistics of the action of $\Gamma$ on small measure subsets of…

Dynamical Systems · Mathematics 2025-12-11 Mikołaj Frączyk

We define the notion of entropy for a cross section of an action of continuous amenable group and relate it to the entropy of the ambient action. As a result, we are able to answer a question of J.P. Thouvenot about completely positive…

Dynamical Systems · Mathematics 2009-11-10 Nir Avni

The article considers generic extensions of measure-preserving actions. We prove that the P-entropy of the generic extensions with finite P-entropy is infinite. This is exploited to obtain the result by Austin, Glasner, Thouvenot, and Weiss…

Dynamical Systems · Mathematics 2023-07-11 Valery V. Ryzhikov

We prove a max-min theorem for weak containment in the context of algebraic actions. Namely, we show that given an algebraic action of $G$ on $X,$ there is a maximal, closed $G$-invariant subgroup $Y$ of $X$ so that the action of $G$ on $Y$…

Dynamical Systems · Mathematics 2019-07-16 Ben Hayes

Let $G$ be a semisimple Lie group with Haar measure $\mu$ and let $\Gamma$ be an irreducible lattice in $G$. For $g\in G$, we consider left translation $L_g$ acting on $(G\backslash\Gamma,\mu)$. We show that if $L_g$ is $K$ (which is…

Dynamical Systems · Mathematics 2018-12-11 Adam Kanigowski

The exponential growth rate of non polynomially growing subgroups of $GL_d$ is conjectured to admit a uniform lower bound. This is known for non-amenable subgroups, while for amenable subgroups it is known to imply the Lehmer conjecture…

Classical Analysis and ODEs · Mathematics 2022-08-25 Emmanuel Breuillard , Péter P. Varjú

An algebraic $\Gamma$-action is an action of a countable group $\Gamma$ on a compact abelian group $X$ by continuous automorphisms of $X$. We prove that any expansive algebraic action of a finitely generated nilpotent group $\Gamma$ on a…

Dynamical Systems · Mathematics 2017-06-20 Siddhartha Bhattacharya

We consider an isomorphism invariant for measure-preserving systems - types of generalized entropy convergence rates. We show the connections of this invariant with the types of Shannon entropy convergence rates. In the case when they…

Dynamical Systems · Mathematics 2013-09-25 Fryderyk Falniowski

We prove pointwise and maximal ergodic theorems for probability measure preserving (p.m.p.) actions of any countable group, provided it admits an essentially free, weakly mixing amenable action of stable type $III_1$. We show that this…

Dynamical Systems · Mathematics 2011-12-30 Lewis Bowen , Amos Nevo

Let $(M,g)$ be a closed Riemannian spin manifold. The constant term in the expansion of the Green function for the Dirac operator at a fixed point $p\in M$ is called the mass endomorphism in $p$ associated to the metric $g$ due to an…

Differential Geometry · Mathematics 2010-01-21 Andreas Hermann

We investigate Gaussian actions through the study of their crossed-product von Neumann algebra. The motivational result is Chifan and Ioana's ergodic decomposition theorem for Bernoulli actions (Ergodic subequivalence relations induced by a…

Operator Algebras · Mathematics 2012-02-03 Rémi Boutonnet

The last decades have seen growing interest in connecting principles of thermodynamics with methods from analytical mechanics. The thermodynamic formalism has become an inspiring framework in the study of smooth dynamical systems, and…

Statistical Mechanics · Physics 2025-10-23 Aaron Beyen , Christian Maes