Subalqebras of simple AF-alqebras

成果类型:
Article
署名作者:
Schafhauser, Christopher
刊物名称:
ANNALS OF MATHEMATICS
ISSN/ISSBN:
0003-486X
DOI:
10.4007/annals.2020.192.2.1
发表日期:
2020
页码:
309-352
关键词:
C-ASTERISK-ALGEBRAS corona factorization property baum-connes conjecture crossed-products star-algebras UNITARY EQUIVALENCE inductive limits K-THEORY CLASSIFICATION rank
摘要:
It is shown that if A is a separable, exact C*-algebra which satisfies the Universal Coefficient Theorem (UCT) and has a faithful, amenable trace, then A admits a trace-preserving embedding into a simple, unital AF algebra with a unique trace. Modulo the UCT, this provides an abstract characterization of C*-subalgebras of simple, unital AF-algebras. As a consequence, for a countable, discrete, amenable group G acting on a second countable, locally compact, Hausdorff space X, C-o(X) infinity(r) G embeds into a simple, unital AF-algebra if, and only if, X admits a faithful, invariant, Borel, probability measure. Also, for any countable, discrete, amenable group G, the reduced group C*-algebra C-r(*)(G) admits a trace-preserving embedding into the universal UHF-algebra.