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arXiv · 1807.11438

Cox rings and symplectic quotient singularities with torus action

Maksymilian Grab
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Abstract

We develop a method of finding a Cox ring of a crepant resolution of a quotient singularity with a torus action and apply it to examples of symplectic quotient singularities in dimension 4. In addition we obtain a bound on the degrees of homogeneous generators of the Cox ring in a more general setup, based on the multigraded Castelnuovo-Mumford regularity and Kawamata-Viehweg vanishing.

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Maksymilian Grab. 2018-07-30. Cox rings and symplectic quotient singularities with torus action. https://arxiv.org/abs/1807.11438

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