Symmetry in the vanishing of Ext over Gorenstein rings

Craig Huneke; David Jorgensen

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arXiv · 1409.1119

Symmetry in the vanishing of Ext over Gorenstein rings

Craig Huneke·David Jorgensen

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Abstract

We investigate symmetry in the vanishing of Ext for finitely generated modules over local Gorenstein rings. In particular, we define a class of local Gorenstein rings, which we call AB rings, and show that for finitely generated modules $M$ and $N$ over an AB ring $R$, $Ext^i_R(M,N)=0$ for all $i >> 0$ if and only if $Ext^i_R(N,M)=0$ for all $i >> 0$.

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BibTeX RIS

Craig Huneke, David Jorgensen. 2014-09-03. Symmetry in the vanishing of Ext over Gorenstein rings. https://arxiv.org/abs/1409.1119

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