# A topological invariant for continuous fields of Cuntz algebras

@article{Sogabe2020ATI,
title={A topological invariant for continuous fields of Cuntz algebras},
author={T. Sogabe},
journal={Mathematische Annalen},
year={2020},
pages={1-27}
}
• T. Sogabe
• Published 17 February 2020
• Mathematics
• Mathematische Annalen
We wish to investigate continuous fields of the Cuntz algebras. The Cuntz algebras $${\mathcal {O}}_{n+1}, n\ge 1$$ O n + 1 , n ≥ 1 play an important role in the theory of operator algebras, and they are characterized by their K-groups $$K_0({\mathcal {O}}_{n+1})={\mathbb {Z}}_n$$ K 0 ( O n + 1 ) = Z n , the cyclic groups of order $$n\ge 1$$ n ≥ 1 . Since the mod n K-group for a compact Hausdorff space can be realized by the K-group of the trivial continuous field of $${\mathcal {O}}_{n+1}$$ O…
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