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arXiv · 2611.04648

Every classifiable simple C*-algebra has a C*-diagonal

Samuel Evington·Philipp Sibbel
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Abstract

We construct C*-diagonals in all UCT Kirchberg algebras. Together with known constructions of C*-diagonals in the stably finite setting by Xin Li, this shows that every classifiable C*-algebra (in the sense of the Elliott classification programme) has a C*-diagonal. In fact, we show that every UCT Kirchberg algebra admits an untwisted principal étale groupoid model with a finite-dimensional unit space.

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Samuel Evington, Philipp Sibbel. 2026-11-03. Every classifiable simple C*-algebra has a C*-diagonal. https://arxiv.org/abs/2611.04648

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