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arXiv · 2110.13834

Compact moduli of K3 surfaces with a nonsymplectic automorphism

Valery Alexeev·Philip Engel·Changho Han
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Abstract

We construct a modular compactification via stable slc pairs for the moduli spaces of K3 surfaces with a nonsymplectic group of automorphisms under the assumption that some combination of the fixed loci of automorphisms defines an effective big divisor, and prove that it is semitoroidal.

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Valery Alexeev, Philip Engel, Changho Han. 2021-10-26. Compact moduli of K3 surfaces with a nonsymplectic automorphism. https://doi.org/10.1090/btran/136

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