English

Fibring structures of ideals in Roe algebras and their $K$-theories

Operator Algebras 2025-07-25 v2

Abstract

In this paper, we investigate the ideal structure of Roe algebras for metric spaces beyond the scope of Yu's property A. Using the tool of rank distributions, we establish fibring structures for the lattice of ideals in Roe algebras and draw the border of each fibre by introducing the so-called ghostly ideals together with geometric ideals. We also provide coarse geometric criteria to ensure the coincidence of geometric and ghostly ideals and calculate their KK-theories, which can be helpful to analyse obstructions to the coarse Baum-Connes conjecture on the level of ideals.

Keywords

Cite

@article{arxiv.2507.17105,
  title  = {Fibring structures of ideals in Roe algebras and their $K$-theories},
  author = {Zhijie Wang and Benyin Fu and Jiawen Zhang},
  journal= {arXiv preprint arXiv:2507.17105},
  year   = {2025}
}

Comments

Accepted by SCIENTIA SINICA Mathematica (in Chinese)