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arXiv · 1301.1008

Fundamental groups of symplectic singularities

Yoshinori Namikawa
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Abstract

Let (X, ω) be an affine symplectic variety. Assume that X has a C^*-action with positive weights and ωis homogeneous with respect to the C^*-action. We prove that the algebraic fundamental group of the smooth locus X_{reg} is finite. This is a collorary to a more general theorem: If an affine variety X has a C^*action with positive weights and the log pair (X, 0) has klt singularities, then the algebraic fundamental group of X_{reg} is finite.

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Yoshinori Namikawa. 2013-04-11. Fundamental groups of symplectic singularities. https://arxiv.org/abs/1301.1008

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