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On the Castelnuovo-Mumford regularity of products of ideal sheaves

Jessica Sidman
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Abstract

In this paper we give bounds on the Castelnuovo-Mumford regularity of products of ideals and ideal sheaves. In particular, we show that the regularity of a product of ideals is bounded by the sum of the regularities of its factors if the corresponding schemes intersect in a finite set of points. We also show how approximations of sheaves can be used to bound the regularity of an arrangement of two-planes in projective space.

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Jessica Sidman. 2001-11-01. On the Castelnuovo-Mumford regularity of products of ideal sheaves. https://arxiv.org/abs/math/0110184

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