Spherical Orbit Closures in Simple Projective Spaces and Their Normalization
نویسنده
چکیده
Let G be a simply connected semisimple algebraic group over an algebraically closed field k of characteristic 0 and let V be a rational simple G-module. If G/H ⊂ P(V ) is a spherical orbit, set X = G/H ⊂ P(V ) its closure. Then we describe the orbits of X and those of its normalization e X in terms of spherical systems and we give necessary and sufficient conditions so that the normalization e X → X is an homeomorphism; such conditions are automatically fulfilled if the wonderful completion of G/H is strict.
منابع مشابه
Spherical Orbits’ Closures in Simple Projective Spaces and Their Normalization
Let G be a simply connected semisimple algebraic group over an algebraically closed field k of characteristic 0 and let V be a rational simple G-module. If G/H ⊂ P(V ) is a spherical orbit, set X = G/H ⊂ P(V ) its closure. Then we describe the orbits of X and of its normalization e X in terms of spherical systems and we give necessary and sufficient conditions so that the normalization e X → X ...
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