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arXiv · 2608.09517

Classification of anomalous actions of finite groups with the Rokhlin property

Sergio Girón Pacheco·Gábor Szabó
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Abstract

Given a finite group G, we develop a generalization of the fundamental classification of Rokhlin G-actions on C*-algebras to the setting of anomalous G-actions with the Rokhlin property. For Rokhlin G-kernels on C*-algebras covered by the classification program, this implies that the induced G-action on some known invariants determines the conjugacy class. Extending a result of Izumi, we show that G-kernels with the Rokhlin property on Kirchberg algebras are classified by their anomaly and the induced module structure on the K-theory groups. We explore K-theoretic obstructions for the existence of Rokhlin G-kernels on general separable C*-algebras and use these to characterise which G-module structures arise as K-groups of Kirchberg algebras admitting a Rokhlin G-kernel with a given lifting obstruction.

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Sergio Girón Pacheco, Gábor Szabó. 2026-08-10. Classification of anomalous actions of finite groups with the Rokhlin property. https://arxiv.org/abs/2608.09517

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