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arXiv · 1304.5248

Gorenstein in codimension 4 - the general structure theory

Miles Reid
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Abstract

I describe the projective resolution of a codimension 4 Gorenstein ideal, aiming to extend Buchsbaum and Eisenbud's famous result in codimension 3. The main result is a structure theorem stating that the ideal is determined by its (k+1) x 2k matrix of first syzygies, viewed as a morphism from the ambient regular space to the Spin-Hom variety SpH_k in Mat(k+1,2k). This is a general result encapsulating some theoretical aspects of the problem, but, as it stands, is still some way from tractable applications.

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Miles Reid. 2013-04-18. Gorenstein in codimension 4 - the general structure theory. https://arxiv.org/abs/1304.5248

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