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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Detalles Bibliográficos
Autor: Sousa, João Paulo Guardieiro
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2025
País:Brasil
Institución:Universidade de São Paulo (USP)
Repositorio:Biblioteca Digital de Teses e Dissertações da USP
Idioma:inglés
OAI Identifier:oai:teses.usp.br:tde-05082025-170919
Acceso en línea:https://www.teses.usp.br/teses/disponiveis/55/55135/tde-05082025-170919/
Access Level:acceso abierto
Palabra clave:Algebraic Curves
Corpos Finitos
Curvas Algébricas
Curvas Elípticas
Elliptic Curves
Elliptic Surfaces.
Finite Fields
Frobenius Classicalidade
Frobenius Classicality
Superfícies Elípticas
Descripción
Sumario: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.