English

A localization algebra approach to the Baum-Connes conjecture for extensions

Operator Algebras 2025-08-26 v2 Group Theory K-Theory and Homology

Abstract

For an extension 1NΓqΓ/N11\rightarrow N \rightarrow \Gamma \xrightarrow{q} \Gamma / N \rightarrow 1 of discrete countable groups, it is known that the Baum-Connes conjecture with coefficients holds for Γ\Gamma if it holds for Γ/N\Gamma / N and q1(F)q^{-1}(F) for any finite subgroup FF of Γ/N\Gamma / N. In this paper, we employ a localization algebra approach to prove this result.

Keywords

Cite

@article{arxiv.2506.18446,
  title  = {A localization algebra approach to the Baum-Connes conjecture for extensions},
  author = {Jianguo Zhang},
  journal= {arXiv preprint arXiv:2506.18446},
  year   = {2025}
}

Comments

We changed the paper's title, since we just used a localization algebra approach to prove a known result for the Baum-Connes conjecturte in this version. In the first version of the paper, there exists an essential mistake in Theorem 3.13 (thanks to Prof. Ralf Meyer and Prof. Shintaro Nishikawa), thus we strengthened the conditions in that theorem

R2 v1 2026-07-01T03:29:06.063Z