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arXiv · 1212.3465

Recursive towers of curves over finite fields using graph theory

Emmanuel Hallouin·Marc Perret
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Abstract

We give a new way to study recursive towers of curves over a finite field, defined from a bottom curve $\Cun$ and a correspondence $\Cdeux$ on $\Cun$.In particular, we study their asymptotic behavior. A close examination of singularities leads to a necessary condition for a tower to be asymptotically good. Then, spectral theory on a directed graph and considerations on the class of $\Cdeux$ in $\NS (\Cun \times \Cun)$ lead to the fact that, under some mild assumptions, a recursive tower which does not reach Drinfeld-Vladut bound cannot be optimal in Tsfasmann-Vladut sense. Results are applied to the Bezerra-Garcia-Stichtenoth tower along the paper for illustration.

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Emmanuel Hallouin, Marc Perret. 2012-12-14. Recursive towers of curves over finite fields using graph theory. https://arxiv.org/abs/1212.3465

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