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arXiv · 1210.5882

Vanishing of cohomology over complete intersection rings

Arash Sadeghi
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Abstract

Let R be a complete intersection ring and let M and N be R-modules. It is shown that the vanishing of Ext^i_R(M,N) for a certain number of consecutive values of i starting at n forces the complete intersection dimension of M to be at most n-1. We also estimate the complete intersection dimension of the dual of M, in terms of vanishing of the cohomology modules, Ext^i_R(M,N).

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Arash Sadeghi. 2013-03-30. Vanishing of cohomology over complete intersection rings. https://arxiv.org/abs/1210.5882

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