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arXiv · 2205.15238

Variation of stability for moduli spaces of unordered points in the plane

Patricio Gallardo·Benjamin Schmidt
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Abstract

We study compactifications of the moduli space of unordered points in the plane via variation of GIT quotients of their corresponding Hilbert scheme. Our VGIT considers linearizations outside the ample cone and within the movable cone. For that purpose, we use the description of the Hilbert scheme as a Mori dream space, and the moduli interpretation of its birational models via Bridgeland stability. We determine the GIT walls associated with curvilinear zero-dimensional schemes, collinear points, and schemes supported on a smooth conic. For seven points, we study a compactification associated with an extremal ray of the movable cone, where stability behaves very differently from the Chow quotient. Lastly, a complete description for five points is given.

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Patricio Gallardo, Benjamin Schmidt. 2022-05-30. Variation of stability for moduli spaces of unordered points in the plane. https://arxiv.org/abs/2205.15238

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