Invariant subspaces of some function spaces on symmetric spaces. I

The article describes the construction of closed linear subspaces of some function spaces on the symmetric space $M=\operatorname{SU}(n,1)/U(n)$ that are invariant with respect to the natural quasiregular representation of the group $\operatorname{SU}(n,1)$. The function spaces considered include, in particular, the spaces $C^d(M)$ $(d=0,1,\dots,\infty)$ and spaces of functions of exponential growth on $M$.