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The degree of the bicanonical map of a surface with $p_g=0$

Margarida Mendes Lopes·Rita Pardini
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Abstract

In this note it is shown that, given a smooth minimal complex surface of general type S with p_g(S)=0, K^2_S=3, for which the bicanonical map is a morphism, then the degree of the bicanonical map of S is not equal to 3. This completes our earlier results, showing that if X is a minimal surface of general type with p_g=0, K^2>=3 such that |2K_X| is free, then the bicanonical map of X can have degree 1, 2 or 4.

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BibTeXRIS

Margarida Mendes Lopes, Rita Pardini. 2006-02-14. The degree of the bicanonical map of a surface with $p_g=0$. https://arxiv.org/abs/math/0505231

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