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ON ODA’S PROBLEM AND SPECIAL LOCI

Published online by Cambridge University Press:  12 November 2024

Benjamin Collas*
Affiliation:
Research Institute for Mathematical Sciences Kyoto University, Kyoto 606-8502, Japan ([email protected])
Séverin Philip
Affiliation:
Research Institute for Mathematical Sciences Kyoto University, Kyoto 606-8502, Japan ([email protected])

Abstract

Oda’s problem, which deals with the fixed field of the universal monodromy representation of moduli spaces of curves and its independence with respect to the topological data, is a central question of anabelian arithmetic geometry. This paper emphasizes the stack nature of this problem by establishing the independence of monodromy fields with respect to finer special loci data of curves with symmetries, which we show provides a new proof of Oda’s prediction.

Type
Research Article
Copyright
© The Author(s), 2024. Published by Cambridge University Press

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Footnotes

Supported by JSPS KAKENHI Grant Number 22F22015 (S. Philip) and by the Research Institute for Mathematical Sciences, Kyoto University. This work is part of the “Arithmetic and Homotopic Galois Theory” project, supported by the CNRS France-Japan AHGT International Research Network between the RIMS Kyoto University, the LPP of Lille University, and the DMA of ENS PSL.

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