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arXiv · 1603.03604

The $a$-numbers of Fermat and Hurwitz curves

Maria Montanucci·Pietro Speziali
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Abstract

For an algebraic curve $\mathcal{X}$ defined over an algebraically closed field of characteristic $p >0$, the $a$-number $a(\mathcal{X})$ is the dimension of the space of exact holomorphic differentials on $\mathcal{X}$. We compute the $a$-number for an infinite families of Fermat and Hurwitz curves. Our results apply to Hermitian curves giving a new proof for a previous result of Gross.

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Maria Montanucci, Pietro Speziali. 2016-03-11. The $a$-numbers of Fermat and Hurwitz curves. https://arxiv.org/abs/1603.03604

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