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arXiv · 2206.05812

The Improved New Intersection Theorem revisited

Lars Winther Christensen·Luigi Ferraro
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Abstract

We prove a generalized version of Evans and Griffith's Improved New Intersection Theorem: Let I be an ideal in a local ring R. If a finite free R-complex, concentrated in nonnegative degrees, has I-torsion homology in positive degrees, and the homology in degree 0 has an I-torsion minimal generator, then the length of the complex is at least dim R - dim R/I. This improves the bound ht I obtained by Avramov, Iyengar, and Neeman in 2018.

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Lars Winther Christensen, Luigi Ferraro. 2022-06-12. The Improved New Intersection Theorem revisited. https://arxiv.org/abs/2206.05812

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