English

Separation profiles, isoperimetry, growth and compression

Group Theory 2019-10-28 v1 Metric Geometry Probability

Abstract

We give lower and upper bounds for the separation profile (introduced by Benjamini, Schramm & Tim\'ar) for various graphs using the isoperimetric profile, growth and Hilbertian compression. For graphs which have polynomial isoperimetry and growth, we show that the separation profile Sep(n)\mathrm{Sep}(n) is also bounded by powers of nn. For many amenable groups, we show a lower bound in n/log(n)an/ \log(n)^a and, for any group which has a non-trivial compression exponent in an LpL^p-space, an upper bound in n/log(n)bn/ \log(n)^b. We show that solvable groups of exponential growth cannot have a separation profile bounded above by a sublinear power function. In an appendix, we introduce the notion of local separation, with applications for percolation clusters of Zd \mathbb{Z}^{d} and graphs which have polynomial isoperimetry and growth.

Keywords

Cite

@article{arxiv.1910.11733,
  title  = {Separation profiles, isoperimetry, growth and compression},
  author = {Corentin Le Coz and Antoine Gournay},
  journal= {arXiv preprint arXiv:1910.11733},
  year   = {2019}
}

Comments

41 pages

R2 v1 2026-06-23T11:54:58.260Z