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arXiv · 1411.3393

Ubiquity of complete intersection liaison classes

Mark Johnson·Paolo Mantero
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Abstract

In this paper, we provide constructions to enumerate large numbers of CI-liaison classes. To this end, we introduce a liaison invariant and prove several results concerning it, notably that it commutes with hypersurface sections. This theory is applied to the CI-liaison classes of ruled joins of projective schemes, yielding strong obstructions for such joins to lie in the same liaison class. A second construction arises from the actions of automorphisms on liaison classes, allowing the enumeration of many liaison classes of perfect ideals of codimension at least three.

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Mark Johnson, Paolo Mantero. 2014-11-12. Ubiquity of complete intersection liaison classes. https://arxiv.org/abs/1411.3393

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