The subgroup $PSL(2,R)$ is spherical in the group of diffeomorphisms of the circle

Yury A. Neretin

doi:10.4213/faa3227, 10.1007/s10688-016-0143-2

paper

The subgroup $P S L (2, R)$ is spherical in the group of diffeomorphisms of the circle

arXiv:1501.05820 · doi:10.4213/faa3227, 10.1007/s10688-016-0143-2

Abstract

We show that the group $P S L (2, R)$ is a spherical subgroup in the group of $C^{3}$ -diffeomorphisms of the circle. Also, the group of automorphisms of a Bruhat--Tits tree is a spherical subgroup in the group of hierarchomorphisms of the tree.

arXiv comment6pp, typos were corrected

The subgroup PSL(2,R) is spherical in the group of diffeomorphisms of the circle

Abstract

The subgroup $P S L (2, R)$ is spherical in the group of diffeomorphisms of the circle