The Luna-Vust Theory of Spherical Embeddings
نویسنده
چکیده
The work of Krämer, Luna, Vust, Brion and others [Krä,LV,BLV,BP] established the importance of a very distinguished class of homogeneous varieties G/H, those which are now called spherical. Such varieties are homogeneous for a connected reductive group G and are characterized by many equivalent properties, the most important being (see [BLV]): — Any Borel subgroup B of G has an open orbit in G/H. — Every equivariant completion of G/H contains only finitely many orbits. — For every irreducible G-module V and any character χ of H
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