Mathematics – Logic
Scientific paper
2011-07-08
Mathematics
Logic
Scientific paper
If $G$ is a Polish group and $\Gamma$ is a countable group, denote by $\Hom(\Gamma, G)$ the space of all homomorphisms $\Gamma \to G$. We study properties of the group $\cl{\pi(\Gamma)}$ for the generic $\pi \in \Hom(\Gamma, G)$, when $\Gamma$ is abelian and $G$ is one of the following three groups: the unitary group of an infinite-dimensional Hilbert space, the automorphism group of a standard probability space, and the isometry group of the Urysohn metric space. Under mild assumptions on $\Gamma$, we prove that in the first case, there is (up to isomorphism of topological groups) a unique generic $\cl{\pi(\Gamma)}$; in the other two, we show that the generic $\cl{\pi(\Gamma)}$ is extremely amenable. We also show that if $\Gamma$ is torsion-free, the centralizer of the generic $\pi$ is as small as possible, extending a result of King from ergodic theory.
Melleray Julien
Tsankov Todor
No associations
LandOfFree
Generic representations of abelian groups and extreme amenability does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Generic representations of abelian groups and extreme amenability, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Generic representations of abelian groups and extreme amenability will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-222700