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Related papers: Quasi-actions on trees and Property (QFA)

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It is known that for $\sigma$-compact groups Kazhdan's Property $(T)$ is equivalent to Serre's Property $(FH)$. Generalized versions of those properties, called properties $(T_{B})$ and $(F_{B})$, can be defined in terms of the isometric…

Group Theory · Mathematics 2016-11-18 Alan Czuron

Nous donnons des r\'esultats d'\'equidistribution d'\'el\'ements de corps de fonctions sur des corps finis, et d'irrationnels quadratiques sur ces corps, dans leurs corps locaux compl\'et\'es. Nous d\'eduisons ces r\'esultats de…

Number Theory · Mathematics 2025-10-30 Anne Broise-Alamichel , Jouni Parkkonen , Frédéric Paulin

Property FW is a natural combinatorial weakening of Kazhdan's Property T. We prove that the group of piecewise homographic self-transformations of the real projective line, has "few" infinite subgroups with Property FW. In particular, no…

Dynamical Systems · Mathematics 2021-05-11 Yves Cornulier

We continue the study of prime simple modules for quantum affine algebras from the perspective of $q$-fatorization graphs. In this paper we establish several properties related to simple modules whose $q$-factorization graphs are afforded…

Representation Theory · Mathematics 2024-06-12 Adriano Moura , Clayton Silva

We define a relative property A for a countable group with respect to a finite family of subgroups. Many characterizations for relative property A are given. In particular a relative bounded cohomological characterization shows that if a…

Group Theory · Mathematics 2012-09-17 Ronghui Ji , Crichton Ogle , Bobby Ramsey

We characterise the bracketing identities satisfied by linear quasigroups with the help of certain equivalence relations on binary trees that are based on the left and right depths of the leaves modulo some integers. The numbers of…

Combinatorics · Mathematics 2023-10-16 Erkko Lehtonen , Tamás Waldhauser

We provide an expository account of some of the Hopf algebras that can be defined using trees, labeled trees, ordered trees and heap ordered trees. We also describe some actions of these Hopf algebras on algebra of functions.

Rings and Algebras · Mathematics 2007-11-27 Robert L. Grossman , Richard G. Larson

Generalized trees, we call them O-trees, are defined as hierarchical partial orders, i.e., such that the elements larger than any one are linearly ordered. Quasi-trees are, roughly speaking, undirected O-trees. For O-trees and quasi-trees,…

Logic in Computer Science · Computer Science 2025-03-05 Bruno Courcelle

It is shown that for any action of a finitely presented group $G$ on an $\R$-tree, there is a decomposition of $G$ as the fundamental group of a graph of groups related to this action. If the action of $G$ on $T$ is non-trivial, i.e. there…

Geometric Topology · Mathematics 2022-02-23 M. J. Dunwoody

We show that many nice properties of a theory $T$ follow from the corresponding properties of its reducts to finite subsignatures. If $\{ T_i \}_{i \in I}$ is a directed family of conservative expansions of first-order theories and each…

Logic · Mathematics 2015-08-26 Alice Medvedev

A congruence of the weak order is simple if its quotientope is a simple polytope. We provide an alternative elementary proof of the characterization of the simple congruences in terms of forbidden up and down arcs. For this, we provide a…

Combinatorics · Mathematics 2026-05-07 Emily Barnard , Jean-Christophe Novelli , Vincent Pilaud

In this article, we introduce the concept of partial actions of a group $G$ on quivers and demonstrate that for any given partial action of G on a quiver $\Gamma$, there exists another quiver, $\Gamma'$ with a full $G$-action. This is an…

Representation Theory · Mathematics 2025-10-27 Wagner Cortes , Eduardo N. Marcos

We study the relation (and differences) between stability and Property (S) in the simple and stably finite framework. This leads us to characterize stable elements in terms of its support, and study these concepts from different sides :…

Operator Algebras · Mathematics 2021-02-19 Joan Bosa

Given an action by a finitely generated group G on a locally finite tree T, we view points of the visual boundary \partialT as directions in T and use {\rho} to lift this sense of direction to G. For each point E \in \partialT, this allows…

Group Theory · Mathematics 2011-11-04 Keith Jones

An automaton is called reachable if every state is reachable from the initial state. This notion has been generalized coalgebraically in two ways: first, via a universal property on pointed coalgebras, namely, that a reachable coalgebra has…

Logic in Computer Science · Computer Science 2026-01-23 Thorsten Wißmann , Bálint Kocsis , Jurriaan Rot , Ruben Turkenburg

Simon's factorization theorem is a celebrated tool in algebraic automata theory, providing bounded-depth decompositions of words with respect to morphisms into finite semigroups. We develop an analogue of Simon's theorem for \emph{forests}…

Formal Languages and Automata Theory · Computer Science 2026-05-12 Shaull Almagor , Michaël Cadilhac , Asaf Shoham

The concept of pseudo q-factorization graphs was recently introduced by the last two authors as a combinatorial language which is suited for capturing certain properties of Drinfeld polynomials. Using certain known representation theoretic…

Representation Theory · Mathematics 2025-10-13 Matheus Brito , Adriano Moura , Clayton Silva

Since being isolated by Viale and Weiss in 2009, the Guessing Model Property has emerged as a particularly prominent and powerful consequence of the Proper Forcing Axiom. In this paper, we investigate connections between variations of the…

Logic · Mathematics 2023-03-03 Chris Lambie-Hanson , Šárka Stejskalová

We give a characterization for two different concepts of quasi-analyticity in Carleman ultraholomorphic classes of functions of several variables in polysectors. Also, working with strongly regular sequences, we establish generalizations of…

Complex Variables · Mathematics 2010-01-25 Alberto Lastra , Javier Sanz

In this paper we analyse some questions concerning trees on $\kappa$, both for the countable and the uncountable case, and the connections with Cohen reals. In particular, we provide a proof for one of the implications left open in…

Logic · Mathematics 2020-04-24 Giorgio Laguzzi , Brendan Stuber-Rousselle
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