English

Non-stable K-theory and extremally rich C*-algebras

Operator Algebras 2017-06-09 v2

Abstract

We consider the properties weak cancellation, K_1-surjectivity, good index theory, and K_1-injectivity for the class of extremally rich C*-algebras, and for the smaller class of isometrically rich C*-algebras. We establish all four properties for isometrically rich C*-algebras and for extremally rich C*-algebras that are either purely infinite or of real rank zero, K_1-injectivity in the real rank zero case following from a prior result of H. Lin. We also show that weak cancellation implies the other properties for extremally rich C*-algebras and that the class of extremally rich C*-algebras with weak cancellation is closed under extensions. Moreover, we consider analogous properties which replace the group K_1(A) with the extremal K-set K_e(A) as well as two versions of K_0-surjectivity.

Keywords

Cite

@article{arxiv.0708.3078,
  title  = {Non-stable K-theory and extremally rich C*-algebras},
  author = {Lawrence G. Brown and Gert K. Pedersen},
  journal= {arXiv preprint arXiv:0708.3078},
  year   = {2017}
}

Comments

This is the last of our joint papers and has been accepted for publication subject to correcting two typographical errors, which are corrected in this revised version