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arXiv · 2412.16087

Lie ideals in properly infinite C*-algebras

Hannes Thiel
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Abstract

We show that every Lie ideal in a unital, properly infinite C*-algebra is commutator equivalent to a unique two-sided ideal. It follows that the Lie ideal structure of such a C*-algebra is concisely encoded by its lattice of two-sided ideals. This answers a question of Robert in this setting. We obtain similar structure results for Lie ideals in unital, real rank zero C*-algebras without characters. As an application, we show that every Lie ideal in a von Neumann algebra is related to a unique two-sided ideal, which solves a problem of Brešar, Kissin, and Shulman.

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Hannes Thiel. 2025-06-13. Lie ideals in properly infinite C*-algebras. https://arxiv.org/abs/2412.16087

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