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arXiv · 1401.7502

Xiao's conjecture for general fibred surfaces

Miguel Ángel Barja·Víctor González-Alonso·Juan Carlos Naranjo
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Abstract

We prove that the genus $g$, the relative irregularity $q_f$ and the Clifford index $c_f$ of a non-isotrivial fibration $f$ satisfy the inequality $q_f \leq g - c_f$. This gives in particular a proof of Xiao's conjecture for fibrations whose general fibres have maximal Clifford index.

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Miguel Ángel Barja, Víctor González-Alonso, Juan Carlos Naranjo. 2015-07-07. Xiao's conjecture for general fibred surfaces. https://arxiv.org/abs/1401.7502

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