Equidecomposition in cardinal algebras
Tom 253 / 2021
Fundamenta Mathematicae 253 (2021), 197-204
MSC: Primary 08A65; Secondary 28A60.
DOI: 10.4064/fm922-6-2020
Opublikowany online: 21 September 2020
Streszczenie
Let $\Gamma $ be a countable group. A classical theorem of Thorisson states that if $X$ is a standard Borel $\Gamma $-space and $\mu $ and $\nu $ are Borel probability measures on $X$ which agree on every $\Gamma $-invariant subset, then $\mu $ and $\nu $ are equidecomposable, i.e. there are Borel measures $(\mu _\gamma )_{\gamma \in \Gamma }$ on $X$ such that $\mu = \sum _\gamma \mu _\gamma $ and $\nu = \sum _\gamma \gamma \mu _\gamma $. We establish a generalization of this result to cardinal algebras.