Obstructions to deforming curves on a 3-fold, I: A generalization of Mumford's example and an application to Hom schemes

Shigeru Mukai; Hirokazu Nasu

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arXiv · math/0609284

Obstructions to deforming curves on a 3-fold, I: A generalization of Mumford's example and an application to Hom schemes

Shigeru Mukai·Hirokazu Nasu

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Abstract

We give a sufficient condition for a first order infinitesimal deformation of a curve on a 3-fold to be obstructed. As application we construct generically non-reduced components of the Hilbert schemes of uniruled 3-folds and the Hom scheme from a general curve of genus five to a general cubic 3-fold.

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Shigeru Mukai, Hirokazu Nasu. 2006-09-11. Obstructions to deforming curves on a 3-fold, I: A generalization of Mumford's example and an application to Hom schemes. https://arxiv.org/abs/math/0609284

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