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Etale homotopy types of moduli stacks of algebraic curves with symmetries

Paola Frediani·Frank Neumann
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Abstract

Using the machinery of etale homotopy theory a' la Artin-Mazur we determine the etale homotopy types of moduli stacks over $\bar{\Q}$ parametrizing families of algebraic curves of genus g greater than 1 endowed with an action of a finite group G of automorphisms, which comes with a fixed embedding in the mapping class group, such that in the associated complex analytic situation the action of G is precisely the differentiable action induced by this specified embedding of G in the mapping class group.

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Paola Frediani, Frank Neumann. 2004-04-21. Etale homotopy types of moduli stacks of algebraic curves with symmetries. https://arxiv.org/abs/math/0404387

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