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arXiv · 1604.08684

Topological Orbit Dimension of MF $C^*$-algebras

Qihui Li·Don Hadwin·Weihua Li·Junhao Shen
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Abstract

This paper is a continuation of our work on D. Voiculescu's topological free entropy dimension in unital C*-algebras. In this paper we first prove the topological free entropy dimension of a MF-nuclear and inner QD algebra is irrelevant to its generating family. Then we give the relation between the topological orbit dimension $K_{top}^2$ and the modified free orbit dimension$ K_2^2$ by using MF-traces. We also introduce a new invariant $K_{top}^3$ which is a modification of the topological orbit dimension $K_{top}^2$ when$ K_{top}^2$ is defined. As the applications of $K_{top}^3$, We prove that$ K_{top}^3(A)=0$ if A has property $ c^*-Γ$ and has no finite-dimensional representations. We also give the definition of property MF-c^*-Γ. We then conclude that, for the unital MF $ C^*$-algebra with no finite-dimensional representations, if A has property MF-c*-Γ, then $K_{top}^3(A)=0$.

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Qihui Li, Don Hadwin, Weihua Li, Junhao Shen. 2016-10-04. Topological Orbit Dimension of MF $C^*$-algebras. https://arxiv.org/abs/1604.08684

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