Restrictions on the Singularity Content of a Fano Polygon

Daniel Cavey

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arXiv · 1808.06476

Restrictions on the Singularity Content of a Fano Polygon

Daniel Cavey

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Abstract

We determine restrictions on the singularity content of a Fano polygon, or equivalently of certain orbifold del Pezzo surfaces. We establish bounds on the maximum number of 1/R(1,1) singularities in the basket of residual singularities. In particular, there are no Fano polygons without T-singularities and with a basket given by (i) {k x 1/R(1,1)} where k is a positive integer and R>4, or (ii) {1/R1(1,1), 1/R2(1,1), 1/R3(1,1)}.

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Daniel Cavey. 2018-08-20. Restrictions on the Singularity Content of a Fano Polygon. https://arxiv.org/abs/1808.06476

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