English

Applications conformes {\`a} grande {\'e}chelle

Differential Geometry 2017-11-28 v2 Metric Geometry

Abstract

Roughly speaking, let us say that a map between metric spaces is large scale conformal if it maps packings by large balls to large quasi-balls with limited overlaps. This quasi-isometry invariant notion makes sense for finitely generated groups. Inspired by work by Benjamini and Schramm, we show that under such maps, some kind of dimension increases: exponent of volume growth for nilpotent groups, conformal dimension of the ideal boundary for hyperbolic groups. A purely metric space notion of {\ell} p-cohomology plays a key role.

Keywords

Cite

@article{arxiv.1604.01195,
  title  = {Applications conformes {\`a} grande {\'e}chelle},
  author = {Pierre Pansu},
  journal= {arXiv preprint arXiv:1604.01195},
  year   = {2017}
}

Comments

New version stresses that results apply to coarse embeddings and includes a reference to recent work by Hume-Mackay-Tessera

R2 v1 2026-06-22T13:25:25.059Z