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Quadratic sheaves and self-linkage

Gianfranco Casnati·Fabrizio Catanese
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Abstract

Generalizing an old result proved by P. Rao [see MR 83i:14025] for arithmetically Cohen-Macaulay, self-linked subschemes of codimension 2 in the projective n-space P, we give a characterization of self-linked pure subschemes of codimension 2 in P satisfying a necessary parity condition, in characteristic different from 2. We make use of the theory of quadratic sheaves described in a previous paper of the authors [see MR 99h:14044].

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Gianfranco Casnati, Fabrizio Catanese. 2001-06-13. Quadratic sheaves and self-linkage. https://arxiv.org/abs/math/0106104

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