English

Open Projections and Suprema in the Cuntz Semigroup

Operator Algebras 2015-08-31 v3 Functional Analysis

Abstract

We provide a new and concise proof of the existence of suprema in the Cuntz semigroup using the open projection picture of the Cuntz semigroup initiated by Ortega, Rordam and Thiel. Our argument is based on the observation that the supremum of a countable set of open projections in the bidual of a C*-algebra A is again open and corresponds to the generated hereditary sub-C*-algebra of A.

Keywords

Cite

@article{arxiv.1411.5619,
  title  = {Open Projections and Suprema in the Cuntz Semigroup},
  author = {Joan Bosa and Gabriele Tornetta and Joachim Zacharias},
  journal= {arXiv preprint arXiv:1411.5619},
  year   = {2015}
}

Comments

11 pages; we fixed a gap in one of the lemmas of the previous version