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arXiv · 1909.03780

Relative VGIT and an application to degenerations of Hilbert schemes

Lars H. Halle·Klaus Hulek·Ziyu Zhang
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Abstract

We generalize the classical semi-continuity theorem for GIT (semi)stable loci under variations of linearizations to a relative situation of an equivariant projective morphism from X to an affine base S. As an application to moduli problems, we consider degenerations of Hilbert schemes, and give a conceptual interpretation of the (semi)stable loci of the degeneration families constructed by Gulbrandsen-Halle-Hulek.

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Lars H. Halle, Klaus Hulek, Ziyu Zhang. 2019-09-09. Relative VGIT and an application to degenerations of Hilbert schemes. https://arxiv.org/abs/1909.03780

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