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Related papers: A dynamical proof of Matui's absorption theorem

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Given an ergodic probability measure preserving dynamical system $\G\acts (X,\mu)$, where $\G$ is a finitely generated countable group, we show that the asymptotic growth of the number of finite models for the dynamics, in the sense of…

Dynamical Systems · Mathematics 2011-12-21 Ken Dykema , David Kerr , Mikael Pichot

We give a simple proof that the orbit space of the $p$-subgroup complex of a finite group is contractible using Brown-Forman discrete Morse theory. This result was originally conjectured by Webb and proved by Symonds.

Group Theory · Mathematics 2023-05-10 Benjamin Steinberg

In this note we consider dynamical systems $(X,G)$ on a Cantor set $X$ satisfying some mild technical conditions. The considered class includes, in particular, minimal and transitive aperiodic systems. We prove that two such systems…

Dynamical Systems · Mathematics 2014-02-26 Konstantin Medynets

We define the orbit morphism of partial dynamical systems and prove that an orbit morphism being an isomorphism in the category of partial dynamical systems and orbit morphisms is equivalent to the existence of a continuous orbit…

Operator Algebras · Mathematics 2024-12-06 Gilles G. de Castro , Eun Ji Kang

We prove a dynamical version of the Mordell-Lang conjecture in the context of Drinfeld modules. We use analytic methods similar to the ones employed by Skolem, Chabauty, and Coleman for studying diophantine equations.

Number Theory · Mathematics 2014-01-14 Dragos Ghioca , Thomas J. Tucker

This very short correction notes a gap in an argument of an earlier paper, and also provides a theorem of similar flavor to the main result of that paper.

Group Theory · Mathematics 2022-09-27 Samuel M. Corson

We show that any second-countable \'etale groupoid with polynomial growth is topologically amenable. If its unit space is compact and metrizable, we show that the groupoid has weak $m$-comparison. Thus if the groupoid is also ample and…

Dynamical Systems · Mathematics 2026-05-18 Are Austad , Christian Bönicke

We give an example of a locally compact effective Hausdorff, minimal ample groupoid such that its rational homology differs from the $K$-theory of its reduced groupoid $C^*$-algebra. Moreover, we prove that such example satisfies Matui's…

Operator Algebras · Mathematics 2021-04-06 Eduard Ortega , Alvaro Sanchez

The joint convexity of the map $(X,A) \mapsto X^* A^{-1} X$, an integral representation of operator convex functions, and an observation of Ando are used to obtain a simple proof of both the joint convexity of relative entropy and a trace…

Quantum Physics · Physics 2022-09-07 Mary Beth Ruskai

The paper contains a proof of the conjecture of M. Klin and D. Maru$\breve{\rm s}$i$\breve{\rm c}$ that an automorphism group of a transitive graph contains a permutation, decomposed in cycles of the same length. The proof is based on the…

General Mathematics · Mathematics 2007-05-23 Aleksandr Golubchik

We extract a two-dimensional dynamical system from the theorems of Pappus and Steiner in classical projective geometry. We calculate an explicit formula for this system, and study its elementary geometric properties. Then we use Artin…

Algebraic Geometry · Mathematics 2017-08-15 Jaydeep Chipalkatti , Attila Dénes

In the paper the foundation of the $k$-orbit theory is developed. The theory opens a new simple way to the investigation of groups and multidimensional symmetries. The relations between combinatorial symmetry properties of a $k$-orbit and…

General Mathematics · Mathematics 2007-05-23 Aleksandr Golubchik

In this note, we state and give the main ideas of the proof of a real convexity theorem for group-valued momentum maps. This result is a quasi-Hamiltonian analogue of the O'Shea-Sjamaar theorem in the usual Hamiltonian setting. We prove…

Symplectic Geometry · Mathematics 2009-06-15 Florent Schaffhauser

The Stone-von Neumann-Mackey Theorem for Heisenberg groups associated to locally compact abelian groups is proved using the Peter-Weyl theorem and the theory of Fourier transforms for finite dimensional real vector spaces. A theorem of…

Representation Theory · Mathematics 2011-04-01 Amritanshu Prasad

We consider the notion of strong self-absorption for continuous actions of locally compact groups on the hyperfinite II$_1$-factor and characterize when such an action is tensorially absorbed by another given action on any separably acting…

Operator Algebras · Mathematics 2024-01-30 Gábor Szabó , Lise Wouters

We prove a generalized version of Schmidt's subspace theorem for closed subschemes in general position in terms of suitably defined Seshadri constants with respect to a fixed ample divisor. Our proof builds on previous work by Evertse and…

Number Theory · Mathematics 2019-07-02 Gordon Heier , Aaron Levin

An elementary application of Fatou's lemma gives a strengthened version of the monotone convergence theorem. We call this the convergence from below theorem. We make the case that this result should be better known, and deserves a place in…

Functional Analysis · Mathematics 2014-12-25 J. F. Feinstein

The relationship between geometric and variational principles remains central to Nonlinear Analysis. This paper introduces the \textbf{Orbit-Summability Fixed Point Criterion}, a novel, purely dynamical condition, and establishes its…

Functional Analysis · Mathematics 2025-12-23 Roblêdo Mak's Miranda Sette

Myriad articles are devoted to Mertens's theorem. In yet another, we merely wish to draw attention to a proof by Hardy, which uses a Tauberian theorem of Landau that "leads to the conclusion in a direct and elegant manner". Hardy's proof is…

Number Theory · Mathematics 2013-10-01 Mohammad Bardestani , Tristan Freiberg

In this short note we give an elementary proof for the case of the circle group of the theorem of O. Hatori and E. Sato which states that every measure on the compact abelian group $G$ can be decomposed into a sum of two measures with…

Functional Analysis · Mathematics 2017-05-17 Przemysław Ohrysko