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arXiv · 0710.1152

Convexity properties of gradient maps

Peter Heinzner·Patrick Schuetzdeller
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Abstract

We consider the action of a real reductive group G on a Kaehler manifold Z which is the restriction of a holomorphic action of the complexified group G^C. We assume that the induced action of a compatible maximal compact subgroup U of G^C on Z is Hamiltonian. We have an associated gradient map obtained from a Cartan decomposition of G. For a G-stable subset Y of Z we consider convexity properties of the intersection of the image of Y under the gradient map with a closed Weyl chamber. Our main result is a Convexity Theorem for real semi-algebraic subsets Y of the projective space corresponding to a unitary representation of U.

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Peter Heinzner, Patrick Schuetzdeller. 2007-10-05. Convexity properties of gradient maps. https://arxiv.org/abs/0710.1152

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