English

Discretization of C*-algebras

Operator Algebras 2017-02-16 v2 Functional Analysis

Abstract

We investigate how a C*-algebra could consist of functions on a noncommutative set: a discretization of a C*-algebra AA is a *-homomorphism AMA \to M that factors through the canonical inclusion C(X)(X)C(X) \subseteq \ell^\infty(X) when restricted to a commutative C*-subalgebra. Any C*-algebra admits an injective but nonfunctorial discretization, as well as a possibly noninjective functorial discretization, where MM is a C*-algebra. Any subhomogenous C*-algebra admits an injective functorial discretization, where MM is a W*-algebra. However, any functorial discretization, where MM is an AW*-algebra, must trivialize A=B(H)A = B(H) for any infinite-dimensional Hilbert space HH.

Keywords

Cite

@article{arxiv.1607.03376,
  title  = {Discretization of C*-algebras},
  author = {Chris Heunen and Manuel L. Reyes},
  journal= {arXiv preprint arXiv:1607.03376},
  year   = {2017}
}

Comments

16 pages. This paper supersedes arXiv:1412.1721

R2 v1 2026-06-22T14:52:27.287Z