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Title: Nonamenable simple 𝐢*-algebras with tracial approximation
We construct two types of unital separable simple πΆβˆ—-algebras: 𝐴𝐢1 𝑧 and 𝐴𝐢2 𝑧 , one exact but not amenable, the other nonexact. Both have the same Elliott invariant as the Jiang–Su algebra – namely, 𝐴𝐢𝑖 𝑧 has a unique tracial state,  𝐾0  𝐴𝐢𝑖 𝑧  , 𝐾0  𝐴𝐢𝑖 𝑧  + ,  1 𝐴𝐢𝑖 𝑧  = (Z, Z+, 1), and 𝐾1  𝐴𝐢𝑖 𝑧  = {0} (𝑖 = 1, 2). We show that 𝐴𝐢𝑖 𝑧 (𝑖 = 1, 2) is essentially tracially in the class of separable 𝒡-stable πΆβˆ—-algebras of nuclear dimension 1. 𝐴𝐢𝑖 𝑧 has stable rank one, strict comparison for positive elements and no 2-quasitrace other than the unique tracial state. We also produce models of unital separable simple nonexact (exact but not nuclear) πΆβˆ—-algebras which are essentially tracially in the class of simple separable nuclear𝒡-stable πΆβˆ—-algebras, and the models exhaust all possible weakly unperforated Elliott invariants.We also discuss some basic properties of essential tracial approximation. 1.  more » « less
Award ID(s):
1954600
NSF-PAR ID:
10321031
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Forum mathematicum
Volume:
10
Issue:
e14
ISSN:
0933-7741
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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