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A symplectic approach to van den Ban's convexity theorem

Philip Foth·Michael Otto
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Abstract

Let G be a complex semisimple Lie group and τa complex antilinear involution that commutes with the Cartan involution. If H denotes the connected subgroup of τ-fixed points in G, and K is maximally compact, each H-orbit in G/K can be equipped with a Poisson structure as described by Evens and Lu. We consider symplectic leaves of certain such H-orbits with a natural hamiltonian torus action. A symplectic convexity theorem of Hilgert-Neeb-Plank then leads to van den Ban's convexity theorem for (complex) semisimple symmetric spaces.

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Philip Foth, Michael Otto. 2006-09-25. A symplectic approach to van den Ban's convexity theorem. https://arxiv.org/abs/math/0505063

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