Abstract
In this paper, we will define several new isomorphism invariants for C*-algebras by hyponormal partial isometries and discuss the relation between these invariants and K-theory of C*-algebras. This study was in part inspired by the work of H. Lin and H. Su in the context of \({A\mathcal{T}}\)-algebras. An \({{\rm A}\mathcal{T}}\)-algebra often becomes an extension of an \({{\rm A}\mathbb{T}}\)-algebra by an AF-algebra. We show that there is an essential extension of a simple \({{\rm A}\mathbb{T}}\)-algebra which has real rank zero by an AF-algebra such that it has real rank zero and is not an \({A\mathcal{T}}\)-algebra.
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This article is supported by the National Natural Science Foundation of China (No. 11001131) and the NUST Research Funding (No. 2010ZYTS068).
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Yao, H., Fang, X. Partial isometries and extensions of \({{\rm A}{\mathbb T}}\)-algebras. Arch. Math. 99, 137–146 (2012). https://doi.org/10.1007/s00013-012-0417-8
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DOI: https://doi.org/10.1007/s00013-012-0417-8