Tensor product decompositions and open orbits in multiple flag varieties
  For a connected semisimple algebraic group $G$, we consider some special infinite series of tensor products of simple $G$-modules whose   $G$-fixed point spaces are at most one-dimensional. We prove that their existence is closely related to the existence of open $G$-orbits in multiple flag varieties and address the problem of classifying such series. 
Vladimir L. Popov