Cartan-decomposition subgroups of \(\mathrm{SU}(2,n)\) (Q2730497)

Let \(G\) be a simple linear real Lie group. A closed subgroup \(H\) is called a Cartan decomposition subgroup of \(G\), if \(H\) is connected and if there is a compact subset \(C\) of \(G\) such that \(CHC= G\). The paper under review gives explicit, practical conditions that determine whether \(H\) is a Cartan decomposition subgroup for \(G= \mathrm{SU}(2,n)\). This is a generalization of the work of \textit{H. Oh} and \textit{D. Witte} [Int. Math. Res. Not. 2000, 235--251 (2000; Zbl 0957.22019)] for \(G= \mathrm{SO}(2,n)\).