ar X iv : 0 80 4 . 37 56 v 2 [ m at h . R T ] 1 2 Fe b 20 09 REAL DOUBLE COSET SPACES AND THEIR INVARIANTS
نویسنده
چکیده
Let G be a real form of a complex reductive group. Suppose that we are given involutions σ and θ of G. Let H = G denote the fixed group of σ and let K = G denote the fixed group of θ. We are interested in calculating the double coset space H\G/K. We use moment map and invariant theoretic techniques to calculate the double cosets, especially the ones that are closed. One salient point of our results is a stratification of a quotient of a compact torus over which the closed double cosets fiber as a collection of trivial bundles.
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ar X iv : 0 80 4 . 37 56 v 3 [ m at h . R T ] 1 7 Fe b 20 09 REAL DOUBLE COSET SPACES AND THEIR INVARIANTS
Let G be a real form of a complex reductive group. Suppose that we are given involutions σ and θ of G. Let H = G denote the fixed group of σ and let K = G denote the fixed group of θ. We are interested in calculating the double coset space H\G/K. We use moment map and invariant theoretic techniques to calculate the double cosets, especially the ones that are closed. One salient point of our res...
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