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arXiv · 2508.15575

A Duflo-Moore theorem for ergodic group actions on semifinite von Neumann algebras

Ulrik Enstad·Hannes Wendt
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Abstract

We prove a generalization of the orthogonality relations of Duflo and Moore for ergodic, trace-preserving group actions on von Neumann algebras that are integrable in a suitable sense. We also obtain convolution inequalities that generalize both Young's inequality for convolution on locally compact groups and inequalities for operator-operator convolutions in Werner's quantum harmonic analysis.

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Ulrik Enstad, Hannes Wendt. 2025-08-21. A Duflo-Moore theorem for ergodic group actions on semifinite von Neumann algebras. https://arxiv.org/abs/2508.15575

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