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arXiv · 0804.4624

K_1-injectivity for properly infinite C*-algebras

Etienne Blanchard
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Abstract

One of the main tools to classify \cst-algebras is the study of its projections and its unitaries. It was proved by Cuntz in \cite{Cu81} that if $A$ is a \textit{purely infinite} simple \cst-algebra, then the kernel of the natural map for the unitary group $\U(A)$ to the $K$-theory group $K_1(A)$ is reduced to the connected component $\U^0(A)$, i.e. $A$ is \textit{$K_1$-injective} (see §3). We study in this note a finitely generated \cst-algebra, the $K_1$-injectivity of which would imply the $K_1$-injectivity of all unital \textit{properly infinite} \cst-algebras.

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Etienne Blanchard. 2010-10-12. K_1-injectivity for properly infinite C*-algebras. https://arxiv.org/abs/0804.4624

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