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arXiv · 2310.08768

Rational surfaces with a non-arithmetic automorphism group

Jennifer Li·Sebastián Torres
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Abstract

In arXiv:1008.3825, Totaro gave examples of a K3 surface such that its automorphism group is not commensurable with an arithmetic group, answering a question of Mazur. We give examples of rational surfaces with the same property. Our examples $Y$ are Looijenga pairs, i.e., there is a connected singular nodal curve $D \subset Y$ such that $K_{Y} + D = 0$.

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Jennifer Li, Sebastián Torres. 2023-10-12. Rational surfaces with a non-arithmetic automorphism group. https://arxiv.org/abs/2310.08768

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