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arXiv · 2610.37558

Weak tracial approximation and a weak Rokhlin property for C*-dynamical systems

George A. Elliott·Chun Guang Li·Zhuang Niu·Qingyun Wang
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Abstract

We extend results on tracial approximability of crossed products from the setting of topological dynamical systems to C*-dynamical systems. For actions of discrete amenable groups on unital C*-algebras, we introduce a weak Rokhlin property which leads to a weak tracial approximation of the crossed products by means of finite direct sums of matrix algebras over hereditary subalgebras of the original algebra. Examples are given.

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George A. Elliott, Chun Guang Li, Zhuang Niu, Qingyun Wang. 2026-10-27. Weak tracial approximation and a weak Rokhlin property for C*-dynamical systems. https://arxiv.org/abs/2610.37558

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