A unimodular random graph with large upper growth and no growth

Autor: Mester, Péter, Timár, Ádám
Rok vydání: 2024
Předmět:
Druh dokumentu: Working Paper
Popis: We construct a unimodular random rooted graph with maximal degree $d\geq 3$ and upper growth rate $d-1$, which does not have a growth rate. Ab\'ert, Fraczyk and Hayes showed that for a unimodular random tree, if the upper growth rate is at least $\sqrt{d-1}$, then the growth rate exists, and asked with some scepticism if this may hold for more general graphs. Our construction shows that the answer is negative. We also provide a non-hyperfinite example of a unimodular random graph with no growth rate. This may be of interest in light of a conjecture of Ab\'ert that unimodular Riemannian surfaces of bounded negative curvature always have growth.
Comment: 8 pages
Databáze: arXiv