All 81 crepant resolutions of a finite quotient singularity are hyperpolygon spaces
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Accepted version
Author(s)
Bellamy, Gwyn
Craw, Alastair
Rayan, Steven
Schedler, Travis
Weiss, Hartmut
Type
Journal Article
Abstract
We demonstrate that the linear quotient singularity for the exceptional subgroup G
in Sp(4, C) of order 32 is isomorphic to an affine quiver variety for a 5-pointed star-shaped quiver.
This allows us to construct uniformly all 81 projective crepant resolutions of C4/G as hyperpolygon
spaces by variation of GIT quotient, and we describe both the movable cone and the Namikawa
Weyl group action via an explicit hyperplane arrangement. More generally, for the n-pointed star
shaped quiver, we describe completely the birational geometry for the corresponding hyperpolygon
spaces in dimension 2n − 6; for example, we show that there are 1684 projective crepant resolutions
when n = 6. We also prove that the resulting affine cones are not quotient singularities for n ≥ 6.
in Sp(4, C) of order 32 is isomorphic to an affine quiver variety for a 5-pointed star-shaped quiver.
This allows us to construct uniformly all 81 projective crepant resolutions of C4/G as hyperpolygon
spaces by variation of GIT quotient, and we describe both the movable cone and the Namikawa
Weyl group action via an explicit hyperplane arrangement. More generally, for the n-pointed star
shaped quiver, we describe completely the birational geometry for the corresponding hyperpolygon
spaces in dimension 2n − 6; for example, we show that there are 1684 projective crepant resolutions
when n = 6. We also prove that the resulting affine cones are not quotient singularities for n ≥ 6.
Date Issued
2024-04-01
Date Acceptance
2023-11-06
Citation
Journal of Algebraic Geometry, 2024, 33, pp.757-793
ISSN
1056-3911
Publisher
American Mathematical Society
Start Page
757
End Page
793
Journal / Book Title
Journal of Algebraic Geometry
Volume
33
Copyright Statement
© Copyright 2024 University Press, Inc. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (https://creativecommons.org/licenses/by-nc-nd/4.0/).
Publication Status
Published
Date Publish Online
2024-04-01