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arXiv · 2303.04232

Properly Outer and Strictly Outer Actions of Finite Groups on Prime C*-algebras

Costel Peligrad
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Abstract

An action of a compact, in particular finite group on a C*-algebra is called properly outer if no automorphism of the group that is distinct from identity is implemented by a unitary element of the algebra of local multipliers of the C*-algebra. In this paper I define the notion of strictly outer action (similar to the definition for von Neumann factors in [11]) and prove that for finite groups it is equivalent with proper outerness of the action. For finite abelian groups this is equivalent with other relevant properities of the action.

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Costel Peligrad. 2024-01-02. Properly Outer and Strictly Outer Actions of Finite Groups on Prime C*-algebras. https://doi.org/10.1142/s0129167x24500071

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