Rational surfaces with a non-arithmetic automorphism group
arXiv:2310.08768
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 are Looijenga pairs, i.e., there is a connected singular nodal curve such that .
Final version. To appear in the Bulletin of the London Mathematical Society