Table of contents

  • This session has been presented June 19, 2009.

Description

  • Speaker

    Stéphane Ballet - IML

Nous étudions la notion de suites asymptotiquement exactes de corps de fonctions algébriques introduite par Tsfasman en 1991. Plus précisément, nous construisons explicitement des suites asymptotiquement exactes de corps de fonctions algébriques définis sur des corps finis quelconques, en particulier quand q n'est pas un carré. Ensuite, nous prouvons que ces suites constituent des familles infinies de corps de fonctions algébriques dont le nombre de classes $h$ dépasse strictement la borne de Lachaud - Martin-Deschamps. En particulier, nous construisons une tour asymptotiquement exacte avec densité maximale de corps de fonctions algébriques définis sur $\F_2$ et donnons aussi d'autres exemples.

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