English

The Andreadakis Problem for the McCool groups

Group Theory 2025-03-10 v2 Algebraic Topology

Abstract

In this short paper, we show that the McCool group does not satisfy the Andreadakis equality from degree 77, and we give a lower bound for the size of the difference between the two relevant filtrations. As a consequence, we see that the Andreadakis problem for the McCool group does not stabilize.

Cite

@article{arxiv.2502.20652,
  title  = {The Andreadakis Problem for the McCool groups},
  author = {Jaques Darné and Naoya Enomoto and Takao Satoh},
  journal= {arXiv preprint arXiv:2502.20652},
  year   = {2025}
}

Comments

11 pages

R2 v1 2026-06-28T22:01:04.856Z