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arXiv · 2402.01159

Foldable fans, cscK surfaces and local K-moduli

Carl Tipler
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Abstract

We study the moduli space of constant scalar curvature K\"ahler surfaces around the toric ones. To this aim, we introduce the class of foldable surfaces : smooth toric surfaces whose lattice automorphism group contain a non trivial cyclic subgroup. We classify such surfaces and show that they all admit a constant scalar curvature K\"ahler metric (cscK metric). We then study the moduli space of polarised cscK surfaces around a point given by a foldable surface, and show that it is locally modeled on a finite quotient of a toric affine variety with terminal singularities.

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Carl Tipler. 2024-02-02. Foldable fans, cscK surfaces and local K-moduli. https://doi.org/10.1112/mod.2025.10005

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