SCHWARZ.abs This project concerns three topics:1) (joint with L. Helminck) Commuting involutions of a reductive group and properties of the associated fixed point groups, double coset spaces and invariants. 2) (joint with D. Wehlau) The invariants of four subspaces of n-dimensional space. 3) The structure of differential operators which are invariant under a group, those which are defined on the orbit spaces of the group and the interplay between them. Invariant theory: If one has an object with symmetries (for example, the Euclidean plane with translations and rotations), one is naturally lead to consider those properties of the object (the invariants) which remain the same under these symmetries. Invariant theory is concerned with the classification, description, etc. of invariants.
