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Twisted actions and the obstruction to extending unitary representations of subgroups

Astrid an Huef·Iain Raeburn
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Abstract

Suppose that $G$ is a locally compact group and $π$ is a (not necessarily irreducible) unitary representation of a closed normal subgroup $N$ of $G$ on a Hilbert space $H$. We extend results of Clifford and Mackey to determine when $π$ extends to a unitary representation of $G$ on the same space $H$ in terms of a cohomological obstruction.

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Astrid an Huef, Iain Raeburn. 2003-09-24. Twisted actions and the obstruction to extending unitary representations of subgroups. https://arxiv.org/abs/math/0309396

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