English
Related papers

Related papers: Measure conjugacy invariants for actions of counta…

200 papers

Let $\Gamma$ be a sofic group with a copy of $\mathbb{Z}$ in its center. We construct an uncountable family of pairwise nonisomorphic measure-preserving $\Gamma$ actions with completely positive entropy, none of which is a factor of a…

Dynamical Systems · Mathematics 2016-04-04 Peter Burton

For actions of a sofic group on probability spaces, the entropy has been defined by Bowen, with an extension by Kerr-Li. In particular, when the action is by homeomorphisms of a compact space preserving a given measure, Kerr-Li show one can…

Dynamical Systems · Mathematics 2016-05-17 Ben Hayes

For a locally compact sofic group continuously acting on a compact metric space, we first study the relative sofic entropy and prove an additive inequality relating sofic entropy and relative sofic entropy. Moreover, it is shown that the…

Dynamical Systems · Mathematics 2025-11-25 Xianqiang Li , Zhuowei Liu

We introduce mean dimensions for continuous actions of countable sofic groups on compact metrizable spaces. These generalize the Gromov-Lindenstrauss-Weiss mean dimensions for actions of countable amenable groups, and are useful for…

Dynamical Systems · Mathematics 2013-07-22 Hanfeng Li

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

We study actions of countable discrete groups which are amenable in the sense that there exists a mean on X which is invariant under the action of G. Assuming that G is nonamenable, we obtain structural results for the stabilizer subgroups…

Group Theory · Mathematics 2020-12-16 Robin Tucker-Drob

A measure preserving action of a countably infinite group \Gamma is called totally ergodic if every infinite subgroup of \Gamma acts ergodically. For example, all mixing and mildly mixing actions are totally ergodic. This note shows that if…

Dynamical Systems · Mathematics 2012-08-06 Robin Tucker-Drob

In this paper, we investigate the computability of $\mathcal{G}$-Bernoulli measures, with a particular focus on measures of maximal entropy (MMEs) on coded shift spaces. Coded shifts are natural generalizations of sofic shifts and are…

Dynamical Systems · Mathematics 2026-01-23 Tamara Kucherenko , Marco López , Christian Wolf

Recently Lewis Bowen introduced a notion of entropy for measure-preserving actions of countable sofic groups admitting a generating measurable partition with finite entropy; and then David Kerr and Hanfeng Li developed an operator-algebraic…

Dynamical Systems · Mathematics 2011-09-16 Guo Hua Zhang

We show that for certain classes of actions of Z^d, d >= 2, by automorphisms of the torus any measurable conjugacy has to be affine, hence measurable conjugacy implies algebraic conjugacy; similarly any measurable factor is algebraic, and…

Dynamical Systems · Mathematics 2007-05-23 Anatole Katok , Svetlana Katok , Klaus Schmidt

Building on recent results regarding symmetric probabilistic constructions of countable structures, we provide a method for constructing probability measures, concentrated on certain classes of countably infinite structures, that are…

Logic · Mathematics 2015-11-24 Nathanael Ackerman , Cameron Freer , Jaroslav Nesetril , Rehana Patel

We prove two theorems in the ergodic theory of infinite permutation groups. First, generalizing a theorem of Nessonov for the infinite symmetric group, we show that every non-singular action of a non-archimedean, Roelcke precompact, Polish…

Dynamical Systems · Mathematics 2025-11-07 Todor Tsankov

A sofic measure is the image of a Markov probability measure by a continuous morphism, and can be represented by means of products of matrices $A_n$ that belong to a finite set of nonnegative matrices. To prove that the multifractal…

Functional Analysis · Mathematics 2021-07-30 Alain Thomas

We show that, for countable sofic groups, a Bernoulli action with infinite entropy base has infinite entropy with respect to every sofic approximation sequence. This builds on the work of Lewis Bowen in the case of finite entropy base and…

Dynamical Systems · Mathematics 2010-05-28 David Kerr , Hanfeng Li

Let $G$ be an amenable discrete countable infinite group, $A$ a finite set, and $(\mu_g)_{g\in G}$ a family of probability measures on $A$ such that $\inf_{g\in G}\min_{a\in A}\mu_g(a)>0$. It is shown (among other results) that if the…

Dynamical Systems · Mathematics 2018-07-27 Alexandre I. Danilenko

Recently Lewis Bowen introduced a notion of entropy for measure-preserving actions of a countable sofic group on a standard probability space admitting a generating partition with finite entropy. By applying an operator algebra perspective…

Dynamical Systems · Mathematics 2015-05-18 David Kerr , Hanfeng Li

We prove that if a countable group $\Gamma$ contains infinite commuting subgroups $H, H'\subset \Gamma$ with $H$ non-amenable and $H'$ ``weakly normal'' in $\Gamma$, then any measure preserving $\Gamma$-action on a probability space which…

Group Theory · Mathematics 2007-12-25 Sorin Popa

Let $G$ and $H$ be infinite finitely generated amenable groups. This paper studies two notions of equivalence between actions of such groups on standard Borel probability spaces. They are defined as stable orbit equivalences in which the…

Dynamical Systems · Mathematics 2016-11-08 Tim Austin

The original definition of amenability given by von Neumann in the highly non-constructive terms of means was later recast by Day using approximately invariant probability measures. Moreover, as it was conjectured by Furstenberg and proved…

Functional Analysis · Mathematics 2020-05-29 Theo Bühler , Vadim A. Kaimanovich

Given a countable sofic group $\Gamma$, a finite alphabet $A$, a subshift $X \subseteq A^\Gamma$, and a potential $\phi: X \to \mathbb{R}$, we give sufficient conditions on $X$ and $\phi$ for expressing, in the uniqueness regime, the sofic…

Dynamical Systems · Mathematics 2021-08-16 Raimundo Briceño