Abstract
We show that certain crossed product algebras can be viewed as twisted category algebras associated with finite groupoids. The latter are always isomorphic to products of matrix algebras over twisted group algebras. This has several consequences, in particular in the case where the crossed product algebra is the bismash product associated with a group factorization of a finite group.
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Communicated by: Susan Montgomery
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Danz, S., Erdmann, K. Crossed Products as Twisted Category Algebras. Algebr Represent Theor 18, 281–296 (2015). https://doi.org/10.1007/s10468-014-9493-8
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DOI: https://doi.org/10.1007/s10468-014-9493-8