The spectral form of Koopman representations of the group of measurable functions with values in the circle
Volume 171 / 2023
Colloquium Mathematicum 171 (2023), 303-320
MSC: Primary 22A25; Secondary 22F10, 37A15.
DOI: 10.4064/cm8784-6-2022
Published online: 26 September 2022
Abstract
We compute the spectral form of the Koopman representation induced by a natural boolean action of $L^0(\lambda , \mathbb T)$ identified earlier by the authors. Our computation establishes the sharpness of the constraints on spectral forms of Koopman representations of $L^0(\lambda , \mathbb T)$ previously found by the second author.