A direct approach to co-universal algebras associated to directed graphs

Aidan Sims; Samuel B. G. Webster

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arXiv · 0912.3303

A direct approach to co-universal algebras associated to directed graphs

Aidan Sims·Samuel B. G. Webster

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Abstract

We prove directly that if E is a directed graph in which every cycle has an entrance, then there exists a C*-algebra which is co-universal for Toeplitz-Cuntz-Krieger E-families. In particular, our proof does not invoke ideal-structure theory for graph algebras, nor does it involve use of the gauge action or its fixed point algebra.

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Aidan Sims, Samuel B. G. Webster. 2010-01-12. A direct approach to co-universal algebras associated to directed graphs. https://arxiv.org/abs/0912.3303

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