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arXiv · 2608.25994

Crepant partial resolutions of the nilpotent cone via Hamiltonian reduction

Gwyn Bellamy·Tom Gannon
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Abstract

We show that the nilpotent cone associated to a simply connected semisimple algebraic group, together with all its crepant projective partial resolutions, can be constructed as Hamiltonian reductions of the affine closure of the cotangent bundle of base affine space for suitable choices of stability parameter of a maximal torus. We also realize the base change of the universal Poisson deformation of each of these crepant projective partial resolutions as the GIT quotient of the affine closure of the cotangent bundle of base affine space at the same stability parameter.

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Gwyn Bellamy, Tom Gannon. 2026-08-26. Crepant partial resolutions of the nilpotent cone via Hamiltonian reduction. https://arxiv.org/abs/2608.25994

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