A homological approach for computing the tangent space of the deformation functor of curves with automorphisms

Aristides Kontogeorgis

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A homological approach for computing the tangent space of the deformation functor of curves with automorphisms

Aristides Kontogeorgis

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Abstract

We give an alternative approach to the computation of the dimension of the tangent space of the deformation space of curves with automorphisms. A homological version of the local-global principle similar to the one of J.Bertin, A. Mézard is proved, and a computation in the case of ordinary curves is obtained, by application of the results of S. Nakajima for the Galois module structure of the space of 2-holomorphic differentials on them.

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Aristides Kontogeorgis. 2003-12-24. A homological approach for computing the tangent space of the deformation functor of curves with automorphisms. https://arxiv.org/abs/math/0312447

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