Zobrazeno 1 - 10
of 32
pro vyhledávání: '"BAUMGARTNER, UDO"'
We consider closed, Weyl-transitive groups of automorphisms of thick buildings. For each element of such a group, we derive a combinatorial formula for its scale and establish the existence of a tidy subgroup for it that equals the stabilizer of a si
Externí odkaz:
http://arxiv.org/abs/1710.07881
A scale-multiplicative semigroup in a totally disconnected, locally compact group $G$ is one for which the restriction of the scale function on $G$ is multiplicative. The maximal scale-multiplicative semigroups in groups acting 2-transitively on the
Externí odkaz:
http://arxiv.org/abs/1312.1064
The flat-rank of a totally disconnected, locally compact group G is an integer, which is an invariant of G as a topological group. We generalize the concept of hyperbolic groups to the topological context and show that a totally disconnected, locally
Externí odkaz:
http://arxiv.org/abs/0911.4461
If H is a flat group of automorphisms of finite rank n of a totally disconnected, locally compact group G, then each orbit of H in the metric space B(G) of compact, open subgroups of G is quasi-isometric to n-dimensional euclidean space. In this note
Externí odkaz:
http://arxiv.org/abs/0807.5060
We study Hecke algebras of groups acting on trees with respect to geometrically defined subgroups. In particular, we consider Hecke algebras of groups of automorphisms of locally finite trees with respect to vertex and edge stabilizers and the stabil
Externí odkaz:
http://arxiv.org/abs/0805.3195
Publikováno v:
Groups, Geometry, and Dynamics 2 337-352 (2008)
Let $G$ be an abstract Kac-Moody group over a finite field and $\bar{G}$ be the closure of the image of $G$ in the automorphism group of its positive building. We show that if the Dynkin diagram associated to $G$ is irreducible and neither of spheric
Externí odkaz:
http://arxiv.org/abs/0706.2713
Autor:
Baumgartner, Udo
Let $\Gamma$ be a group which is virtually free of rank at least 2 and let $\mathcal{F}_{td}(\Gamma)$ be the family of totally disconnected, locally compact groups containing $\Gamma$ as a co-compact lattice. We prove that the values of the scale fun
Externí odkaz:
http://arxiv.org/abs/math/0604151
The flat rank of a totally disconnected locally compact group G, denoted flat-rk(G), is an invariant of the topological group structure of G. It is defined thanks to a natural distance on the space of compact open subgroups of G. For a topological Ka
Externí odkaz:
http://arxiv.org/abs/math/0510290
Autor:
Baumgartner, Udo
Let G be the group of rational points of a semisimple algebraic group of rank 1 over a nonarchimedean local field. We improve upon Lubotzky's analysis of graphs of groups describing the action of lattices in G on its Bruhat-Tits tree assuming a condi
Externí odkaz:
http://arxiv.org/abs/math/0302111
Autor:
Baumgartner, Udo, Willis, George A.
We study contraction groups for automorphisms of totally disconnected locally compcat groups using the scale of the automorphism as a tool. The contraction group is shown to be unbounded when the inverse automorphism has non-trivial scale and this sc
Externí odkaz:
http://arxiv.org/abs/math/0302095