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arXiv · 1311.5257

Cylinders in singular del Pezzo surfaces

Ivan Cheltsov·Jihun Park·Joonyeong Won
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Abstract

For each del Pezzo surface $S$ with du Val singularities, we determine whether it admits a $(-K_S)$-polar cylinder or not. If it allows one, then we present an effective $\mathbb{Q}$-divisor $D$ that is $\mathbb{Q}$-linearly equivalent to $-K_S$ and such that the open set $S\setminus\mathrm{Supp}(D)$ is a cylinder. As a corollary, we classify all the del Pezzo surfaces with du Val singularities that admit nontrivial $\mathbb{G}_a$-actions on their affine cones defined by their anticanonical divisors.

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Ivan Cheltsov, Jihun Park, Joonyeong Won. 2013-11-20. Cylinders in singular del Pezzo surfaces. https://doi.org/10.1112/s0010437x16007284

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