PofoliaShared via Pofolia

Journal of the European Mathematical Society· 2026Q1

Free groups are $L^{2}$-subgroup rigid

Andrei Jaikin‐Zapirain

Short summary

Free groups are proven to be $L^{2}$-subgroup rigid, a new concept introduced in this paper.

AI-generated from the title and abstract; the full text is not read.

Key points

  • Introduces the novel concept of $L^{2}$-subgroup rigid groups.
  • Demonstrates that free groups are $L^{2}$-subgroup rigid.
  • Establishes equivalence between compressibility, inertness, strong inertness, and $L^{2}$-independence for finitely generated subgroups of free groups.
  • Confirms conjectures by Dicks and Ventura, and by Antolín and Jaikin-Zapirain.

AI-generated from the title and abstract; the full text is not read.

Abstract

In this paper, we introduce the notion of L^{2} -subgroup rigid groups and demonstrate that free groups are L^{2} -subgroup rigid. As a consequence, we establish the equivalence between compressibility, inertness, strong inertness, and L^{2} -independence for a finitely generated subgroup of a free group, confirming a conjecture by Dicks and Ventura as well as the one by Antolín and Jaikin-Zapirain.

The authors' abstract, as published at the source. Journal of the European Mathematical Society, 2026 · DOI ↗

TakeawaysPremium
Ask the paperFree account

Continue with a free account

Ask the paper: 3 free questions a day about this paper; save it, get its citation, new summaries every day for your field. Takeaways are Premium.

Continue free on the web

Sign in with Google or Apple; no card needed. You come back to this paper.

On your phone:

Field: Geometry and Topology

Geometry and TopologyMathematics