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Benjamin Collas
Action of the Grothendieck-Teichmüller group on torsion elements of full Teichmüller modular groups in genus zero
Journal de théorie des nombres de Bordeaux, 24 no. 3 (2012), p. 605-622, doi: 10.5802/jtnb.813
Article PDF | Reviews MR 3010631 | Zbl 1278.14040

Résumé - Abstract

In this paper we establish the action of the Grothendieck-Teichmüller group $\widehat{GT}$ on the prime order torsion elements of the profinite fundamental group $\pi _1^{geom}(\mathcal{M}_{0,[n]})$. As an intermediate result, we prove that the conjugacy classes of prime order torsion of $\widehat{\pi }_1(\mathcal{M}_{0,[n]})$ are exactly the discrete prime order ones of the $\pi _1(\mathcal{M}_{0,[n]})$.

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