Weak amenability of Lie groups made discrete
arXiv:1612.04280 · doi:10.2140/pjm.2018.297.101
Abstract
We completely characterize connected Lie groups all of whose countable subgroups are weakly amenable. We also provide a characterization of connected semisimple Lie groups that are weakly amenable. Finally, we show that a connected Lie group is weakly amenable if the group is weakly amenable as a discrete group.
Final version. To appear in Pacific Journal of Mathematics