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arXiv · 2507.20931

Quasi-invariant states for the action of compact groups

Maria Elena Griseta
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Abstract

We analyze a natural C*-algebraic definition of G-quasi-invariant states for the automorphic action of a compact group G. We prove that, given a G-quasi-invariant state with central support, when the action of the group G commutes with the modular group, its GNS representation is equivalent to that of a G-invariant state.

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Maria Elena Griseta. 2025-07-28. Quasi-invariant states for the action of compact groups. https://arxiv.org/abs/2507.20931

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