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arXiv · 2204.10797

Numerical properties of exceptional divisors of birational morphisms of smooth surfaces

Vicente Lorenzo·Margarida Mendes Lopes·Rita Pardini
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Abstract

We make a very detailed analysis of the numerical properties of effective divisors whose support is contained in the exceptional locus of a birational morphism of smooth projective surfaces. As an application we extend Miyaoka's inequality on the number of canonical singularities on a projective normal surface with non-negative Kodaira dimension to the non minimal case, obtaining a slightly better result than known extensions by Megyesi and Langer.

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Vicente Lorenzo, Margarida Mendes Lopes, Rita Pardini. 2022-04-22. Numerical properties of exceptional divisors of birational morphisms of smooth surfaces. https://arxiv.org/abs/2204.10797

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