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Champs de Hurwitz

José Bertin·Matthieu Romagny
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Abstract

We give a thorough study of Hurwitz stacks both in Galois and non galois case. The construction is applied to revisit somme classical examples, the stack of stable curves equipped with a level structure, and the stacks of tamely ramified cyclic covers. We exhibit some tautological cohomology classes, and give some universal relations between them. Applications are given to Cornalba-Harris type relations, and to some Hurwitz-Hodge integrals.

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José Bertin, Matthieu Romagny. 2007-01-24. Champs de Hurwitz. https://arxiv.org/abs/math/0701680

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