A model wonderful variety

A quasi-affine homogeneous space under a (complex) reductive group is called a model homogeneous space, if its algebra of regular functions contains every irreducible representation exactly once. For every connected semi-simple group, we introduce a wonderful variety whose orbits are in natural correspondence with the (isomorphisme classes of) model homogeneous spaces. (c) 2007 Elsevier Inc. Tons droits reserves.