C*-diagonals with Cantor spectrum in Cuntz algebras

Samuel Evington; Philipp Sibbel

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arXiv · 2506.22163

C*-diagonals with Cantor spectrum in Cuntz algebras

Samuel Evington·Philipp Sibbel

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Abstract

We prove that there exists a C*-diagonal with Cantor spectrum in the Cuntz algebra $\mathcal{O}_k$ for $2 \le k < \infty$. Our method generalises to an uncountable family of UCT Kirchberg algebras with distinct K-theory. Moreover, we construct principal \'etale groupoid models for these Cuntz algebras and UCT Kirchberg algebras.

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BibTeX RIS

Samuel Evington, Philipp Sibbel. 2025-06-27. C*-diagonals with Cantor spectrum in Cuntz algebras. https://arxiv.org/abs/2506.22163

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