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Concept

Groupe résiduellement fini

Publications associées (15)

Unlikely intersections on the p-adic formal ball

Vlad Serban

We investigate generalizations along the lines of the Mordell-Lang conjecture of the author's p-adic formal Manin-Mumford results for n-dimensional p-divisible formal groups F. In particular, given a finitely generated subgroup (sic) of F(Q(p)) and a close ...

SPRINGER INT PUBL AG2023

Approximating nonabelian free groups by groups of homeomorphisms of the real line

Yash Lodha

We show that for a large class C of finitely generated groups of orientation preserving homeomorphisms of the real line, the following holds: Given a group G of rank k in C, there is a sequence of k-markings (G,S-n), n is an element of N whose limit in the ...

2020

Extensive amenability and a Tits alternative for topological full groups

Nóra Gabriella Szoke

This dissertation investigates the amenability of topological full groups using a property of group actions called extensive amenability. Extensive amenability is a core concept of several amenability results for groups of dynamical origin. We study its pr ...

EPFL2019

Group Approximation in Cayley Topology and Coarse Geometry, Part II: Fibred Coarse Embeddings

Georges Samarine

The objective of this series is to study metric geometric properties of disjoint unions of Cayley graphs of amenable groups by group properties of the Cayley accumulation points in the space of marked groups. In this Part II, we prove that a disjoint union ...

2019

Endo-trivial modules: a reduction to p'-central extensions

Jacques Thévenaz, Caroline Lassueur

We examine how, in prime characteristic p, the group of endotrivial modules of a finite group G and the group of endotrivial modules of a quotient of G modulo a normal subgroup of order prime to p are related. There is always an inflation map, but examples ...

2017

Small Spectral Radius And Percolation Constants On Non-Amenable Cayley Graphs

Motivated by the Benjamini-Schramm non-unicity of percolation conjecture we study the following question. For a given finitely generated nonamenable group Gamma, does there exist a generating set S such that the Cayley graph (Gamma, S), without loops and m ...

American Mathematical Society (AMS)2015

Counting conjugacy classes of cyclic subgroups for fusion systems

Sejong Park

Thévenaz [6] made an interesting observation that the number of conjugacy classes of cyclic subgroups in a finite group G is equal to the rank of the matrix of the numbers of double cosets in G. We give another proof of this fact and present a fusion syste ...

Walter de Gruyter2014

Torsion-free endotrivial modules

Jacques Thévenaz

Let G be a finite group and let T(G) be the abelian group of equivalence classes of endotrivial kG-modules, where k is an algebraically closed field of characteristic p. We investigate the torsion-free part TF(G) of the group T(G) and look for generators o ...

Elsevier2014

Infinite Presentability Of Groups And Condensation

Luc Guyot

We describe various classes of infinitely presented groups that are condensation points in the space of marked groups. A well-known class of such groups consists of finitely generated groups admitting an infinite minimal presentation. We introduce here a l ...

Cambridge University Press2014

Fixed Point Property For Universal Lattice On Schatten Classes

The special linear group G = SLn(Z[x(1), ... , x(k)]) (n at least 3 and k finite) is called the universal lattice. Let n be at least 4, and p be any real number in (1, infinity). The main result is the following: any finite index subgroup of G has the fixe ...

American Mathematical Society (AMS)2013

Endotrivial modules over groups with quaternion or semi-dihedral Sylow 2-subgroup

Jacques Thévenaz

Let G be a finite group with a Sylow 2-subgroup P which is either quaternion or semi-dihedral. Let k be an algebraically closed field of characteristic 2. We prove the existence of exotic endotrivial kG-modules, whose restrictions to P are isomorphic to th ...

European Mathematical Soc2013

Relative Projectivity and Relative Endotrivial Modules

Caroline Lassueur

This dissertation is concerned with modular representation theory of finite groups, and more precisely, with the study of classes of representations, which we shall term relative endotrivial modules. Given a prime number p, a finite group G of order divisi ...

EPFL2012

A lattice in more than two Kac–Moody groups is arithmetic

Nicolas Monod

Let Gamma be an irreducible lattice in a product of n infinite irreducible complete Kac–Moody groups of simply laced type over finite fields. We show that if n>2, then each Kac–Moody groups is in fact a simple algebraic group over a local field and Gamma i ...

2012

Non-unitarisable representations and random forests

Nicolas Monod

We establish a connection between Dixmier's unitarisability problem and the expected degree of random forests on a group. As a consequence, a residually finite group is non-unitarisable if its first L2-Betti number is non-zero or if it is finitely generate ...

Oxford University Press2009

Horocyclic products of trees

Let T-1, ... , T-d be homogeneous trees with degrees q(1) + 1, ... , q(d) + 1 >= 3; respectively. For each tree, let h : Tj -> Z be the Busemann function with respect to a fixed boundary point ( end). Its level sets are the horocycles. The horocyclic produ ...

2008

Publications associées (15)