Counting rational points with Stöhr-Voloch theory and Tate-Shafarevich results

This thesis present some results in the number of rational points of curves defined over finite fields. The first part of this work involves the Stöhr-Voloch theory. We classified the trinomial curves that are Frobenius nonclassical with respect to the morphism of lines, and obtained a formula for t...

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Detalhes bibliográficos
Autor: Sousa, João Paulo Guardieiro
Tipo de documento: tese
Estado:Versão publicada
Data de publicação:2025
País:Brasil
Recursos:Universidade de São Paulo (USP)
Repositório:Biblioteca Digital de Teses e Dissertações da USP
Idioma:inglês
OAI Identifier:oai:teses.usp.br:tde-05082025-170919
Acesso em linha:https://www.teses.usp.br/teses/disponiveis/55/55135/tde-05082025-170919/
Access Level:Acceso aberto
Palavra-chave:Algebraic Curves
Corpos Finitos
Curvas Algébricas
Curvas Elípticas
Elliptic Curves
Elliptic Surfaces.
Finite Fields
Frobenius Classicalidade
Frobenius Classicality
Superfícies Elípticas
Descrição
Resumo:This thesis present some results in the number of rational points of curves defined over finite fields. The first part of this work involves the Stöhr-Voloch theory. We classified the trinomial curves that are Frobenius nonclassical with respect to the morphism of lines, and obtained a formula for the number of its rational points. In addition, we obtained the intersection numbers of the Frobenius nonclassical curves with tangent lines, and some partial results on the Weierstrass semigroups at the places of their function fields. The second part of this work concerns elliptic surfaces which can be seen as elliptic curves over function fields of characteristics 2 and 3. Starting from fixed supersingular elliptic curves over F16 and F9, we obtained formulas for the Mordell-Weil rank of suitable twists of them in Artin-Schreier and Kummer extensions of the function field of a curve. We also studied the singular fibers of the associated elliptic fibration and derived a formula for the geometric Mordell-Weil rank of such twists.