Examples of cylindrical Fano fourfolds

European Journal of Mathematics - Tập 2 - Trang 262-282 - 2015
Yuri Prokhorov1,2,3, Mikhail Zaidenberg4
1Steklov Mathematical Institute, Moscow, Russia
2Faculty of Mechanics and Mathematics, Lomonosov Moscow State University, Moscow, Russia
3Laboratory of Algebraic Geometry, Higher School of Economics, National Research University, Moscow, Russia
4Université Grenoble I, Institut Fourier, UMR 5582 CNRS-UJF, Saint Martin d’Hères Cedex, France

Tóm tắt

We construct four different families of smooth Fano fourfolds with Picard rank 1, which contain cylinders, i.e., Zariski open subsets of the form $$Z\,{\times }\,{\mathbb {A}}^{1}$$ , where Z is a quasiprojective variety. The affine cones over such a fourfold admit effective $${\mathbb {G}}_{{\text {a}}}$$ -actions. Similar constructions of cylindrical Fano threefolds were done previously in the papers by Kishimoto et al. (Affine Algebraic Geometry. CRM Proceedings & Lecture Notes, vol 54, pp 123–163, 2011; Osaka J Math 51(4):1093–1112, 2014).

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