Multiplier representations of discrete groups

Kleppner, Adam

doi:10.1090/S0002-9939-1983-0695278-3

Multiplier representations of discrete groups
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Proc. Amer. Math. Soc. 88 (1983), 371-375 Request permission

Abstract:

Let $\sigma$ be a multiplier on the discrete group $G$. Extending theorems of Kaniuth and Thoma to the case of multiplier representations, we determine when the left regular $\sigma$ representation of $G$ has a type I subrepresentation, and when all the $\sigma$ representations of $G$ are type I.

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