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Related papers: Weak expansiveness for actions of sofic groups

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In this note, presented as a ``community service", followed by the PhD research of the author, we draw the relation between Casselman's theorem regarding the asymptotic behavior of matrix coefficients of reductive algebraic groups over…

Number Theory · Mathematics 2023-03-24 Zahi Hazan

We define a notion of relative soficity for countable groups with respect to a family of groups. A group is sofic if and only if it is relative sofic with respect to the family consisting only of the trivial group. If a group is relatively…

Group Theory · Mathematics 2019-01-11 Ronghui Ji , Crichton Ogle , Bobby Ramsey

We develop a unified approach to defining a point at infinity for an arbitrary space and formalizing convergence to this point. Central to our work is a method to quantify and classify the rates at which functions approach their limits at…

Functional Analysis · Mathematics 2025-12-16 Armen Petrosyan

We introduce and systematically study the concept of a growth tight action. This generalizes growth tightness for word metrics as initiated by Grigorchuk and de la Harpe. Given a finitely generated, non-elementary group $G$ acting on a…

Group Theory · Mathematics 2016-01-20 Goulnara N. Arzhantseva , Christopher H. Cashen , Jing Tao

We study smooth actions by lattices in higher-rank simple Lie groups. Assuming one element of the action acts with positive topological entropy, we prove a number of new rigidity results. For lattices in $\mathrm{SL}(n,\mathbb{R})$ acting…

Dynamical Systems · Mathematics 2025-01-24 Aaron Brown , Homin Lee

We consider the asymptotic expansion of the sum \[S_p(a;w)=\sum_{n=1}^\infty n^{-w}\e^{-an^p}\] as $a\rightarrow 0$ in $|\arg\,a|<\pi/2$ for arbitrary finite $p>$ and $w>0$. Our attention is concentrated mainly on the case when $p$ and $w$…

Classical Analysis and ODEs · Mathematics 2015-03-26 R. B. Paris

In this article we study asymptotic properties of certain discrete groups $\Gamma$ acting by isometries on a product $\XX=\XX_1\times \XX_2$ of locally compact Hadamard spaces. The motivation comes from the fact that Kac-Moody groups over…

Metric Geometry · Mathematics 2014-11-11 Gabriele Link

In this paper we introduce the definition of entropy for a partial $\mathbb{Z}$-action. We show that the definition of partial entropy is an extension of the definition of topological entropy for a $\mathbb Z$-action. We also prove that the…

Dynamical Systems · Mathematics 2021-07-30 A. Baraviera , Daniel Gonçalves , Danilo Royer , Ruy Exel , Fagner B. Rodrigues

Optimal estimates on the asymptotic behaviors of weak solutions both at the origin and at the infinity are obtained to the following quasilinear elliptic equations…

Analysis of PDEs · Mathematics 2015-06-09 Chang-Lin Xiang

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

Bessel and modified Bessel functions of imaginary order $i\nu$ ($\nu >0$) are studied. Asymptotic expansions are derived as $\nu \to \infty$ that are uniformly valid in unbounded complex domains, with error bounds provided. Coupled with…

Classical Analysis and ODEs · Mathematics 2025-07-04 T. M. Dunster

In the first part of this paper, we formulate a general setting in which to study the ergodic theory of differentiable $\mathbb{Z}^d$-actions preserving a Borel probability measure. This framework includes actions by $C^{1+\text{H\"older}}$…

Dynamical Systems · Mathematics 2016-11-01 Aaron Brown , Federico Rodriguez Hertz , Zhiren Wang

This study delves into the exploration of the limiting shape theorem for subadditive processes on finitely generated groups with polynomial growth, commonly referred to as virtually nilpotent groups. Investigating the algebraic structures…

Probability · Mathematics 2024-04-26 Cristian F. Coletti , Lucas R. de Lima

We define and study Poissonian actions of Polish groups as a framework to Poisson suspensions, characterize them spectrally, and provide a complete characterization of their ergodicity. We further construct 'spatial' Poissonian actions,…

Dynamical Systems · Mathematics 2024-09-23 Nachi Avraham-Re'em , Emmanuel Roy

We study periodic points and finitely supported invariant measures for continuous semigroup actions. Introducing suitable notions of periodicity in both topological and measure-theoretical contexts, we analyze the space of invariant Borel…

Dynamical Systems · Mathematics 2025-02-04 Raimundo Briceño , Álvaro Bustos-Gajardo , Miguel Donoso-Echenique

We develop some basic Lipschitz homotopy technique and apply it to manifolds with finite asymptotic dimension. In particular we show that the Higson compactification of a uniformly contractible manifold is mod $p$ acyclic in the finite…

Geometric Topology · Mathematics 2007-05-23 A. Dranishnikov

Asymptotic expansion is constructed and justified for the solution to a nonuniform Neumann boundary-value problem for the Poisson equation with the right-hand side that depends both on longitudinal and transversal variables in a thin…

Analysis of PDEs · Mathematics 2013-04-30 Arsen V. Klevtsovskiy , Taras A. Mel'nyk

Bowen introduced a definition of topological entropy of subset inspired by Hausdorff dimension in 1973 \cite{B}. In this paper we consider the Bowen's entropy for amenable group action dynamical systems and show that under the tempered…

Dynamical Systems · Mathematics 2016-02-29 Dongmei Zheng , Ercai Chen

In this paper we prove that the Euler equation describing the motion of an ideal fluid in $\R^d$ is well-posed in a class of functions allowing spatial asymptotic expansions as $|x|\to\infty$ of any a priori given order. These asymptotic…

Analysis of PDEs · Mathematics 2016-09-27 R. McOwen , Peter Topalov

We study expressive power of continuous logic in classes of metric groups defined by properties of their actions. For example we consider properties non-OB, non-FH and non-FR. The paper substantially extends Section 2 of the paper A.Ivanov,…

Logic · Mathematics 2017-06-27 Aleksander Ivanov