Cayley-Abels graphs and invariants of totally disconnected, locally compact groups

Autor: ARNBJÖRG SOFFÍA ÁRNADÓTTIR, WALTRAUD LEDERLE, RÖGNVALDUR G. MÖLLER
Přispěvatelé: UCL - SST/IRMP - Institut de recherche en mathématique et physique
Jazyk: angličtina
Rok vydání: 2022
Předmět:
Zdroj: Australian Mathematical Society. Journal, Vol. np, no.np, p. 1-33 (2022)
ISSN: 1446-7887
Popis: A connected, locally finite graph $\Gamma $ is a Cayley–Abels graph for a totally disconnected, locally compact group G if G acts vertex-transitively on $\Gamma $ with compact, open vertex stabilizers. Define the minimal degree of G as the minimal degree of a Cayley–Abels graph of G. We relate the minimal degree in various ways to the modular function, the scale function and the structure of compact open subgroups. As an application, we prove that if $T_{d}$ denotes the d-regular tree, then the minimal degree of $\mathrm{Aut}(T_{d})$ is d for all $d\geq 2$ .
Databáze: OpenAIRE