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A connectedness property of algebraic moment maps

Friedrich Knop
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Abstract

Let a connected reductive group G act on the smooth connected variety X. The cotangent bundle of X is a Hamiltonian G-variety. We show that its "total moment map" has connected fibers. This is an expanded version of section 6 of my paper dg-ga/9712010 on Weyl groups of Hamiltonian manifolds.

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Friedrich Knop. 2001-08-09. A connectedness property of algebraic moment maps. https://doi.org/10.1016/s0021-8693(02)00509-4

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