English

(Random) Trees of Intermediate Uniform Growth

Combinatorics 2023-11-10 v3 Probability

Abstract

For every sufficiently well-behaved function g:R0R0g:\mathbb{R}_{\ge 0}\rightarrow\mathbb{R}_{\ge 0} that grows at least linearly and at most exponentially we construct a tree TT of uniform volume growth gg, that is, C1g(r/4)BT(v,r)C2g(4r),for all r0 and vV(T),C_1\cdot g(r/4)\le |B_{T}(v,r)| \le C_2\cdot g(4r),\quad\text{for all $r\ge 0$ and $v\in V(T)$}, where BT(v,r)B_{T}(v,r) denotes the ball of radius rr centered at a vertex vv. In particular, this yields examples of trees of uniform intermediate (i.e. super-polynomial and sub-exponential) volume growth. We use this construction to provide first examples of unimodular random rooted trees of uniform intermediate growth, answering a question by Itai Benjamini. We find a peculiar change in structural properties for these trees at growth rloglogrr^{\log\log r}.

Keywords

Cite

@article{arxiv.2212.01883,
  title  = {(Random) Trees of Intermediate Uniform Growth},
  author = {George Kontogeorgiou and Martin Winter},
  journal= {arXiv preprint arXiv:2212.01883},
  year   = {2023}
}

Comments

23 pages, 6 figures

R2 v1 2026-06-28T07:21:37.859Z