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Combinatorial properties of stable spin curves

Lucia Caporaso·Cinzia Casagrande
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Abstract

The geometry of the moduli space of stable spin curves is studied, with emphasis on its combinatorial properties. In this context, the standard graph theoretic framework is not just a book-keeping device: some purely combinatorial results are proved, having moduli theoretic applications. In particular, certain strata of the moduli space of stable curves are characterized by a (finite) set of integers, measuring the non-reducedness of the scheme of spin curves, and definable in purely graph-theoretical terms.

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Lucia Caporaso, Cinzia Casagrande. 2002-09-02. Combinatorial properties of stable spin curves. https://arxiv.org/abs/math/0209018

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