Effective Artin-Schreier-Witt theory for curves

par Rubén Muñoz--Bertrand (Inria / École polytechnique)

jeudi 16 avr. 2026, 16:00 → 17:00 Europe/Paris

Salle Pellos (1R2-207) (IMT)

In arithmetic geometry, Artin-Schreier-Witt theory gives a way to construct
unramified covers of curves. However, nobody has ever made a full computation
using these techniques. In this talk, we will explain how we implemented an
algorithm which enables one to compute such covers. I will explain the
motivation behind this problem, and the challenges that one faces using this
theory. For our computations, it is necessary to have an algorithm which
computes the fixed points of a Frobenius-semilinear map. I will also explain
how to implement such an algorithm. We will give application of this work,
which is joint with Christophe Levrat (Inria Saclay), to error correcting
codes.