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arXiv · 1611.03280

Rigidity of Ext and Tor with coefficients in residue fields of a commutative noetherian ring

Lars Winther Christensen·Srikanth B. Iyengar·Thomas Marley
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Abstract

Let p be a prime ideal in a commutative noetherian ring R. It is proved that if an R-module M satisfies Tor^R_n(k(p),M) = 0 for some n \geq dim R_p, where k(p) is the residue field at p, then Tor^R_i(k(p),M) = 0 holds for all i \geq n. Similar rigidity results concerning Ext_R^*(k(p),M) are proved, and applications to the theory of homological dimensions are explored.

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Lars Winther Christensen, Srikanth B. Iyengar, Thomas Marley. 2016-11-10. Rigidity of Ext and Tor with coefficients in residue fields of a commutative noetherian ring. https://arxiv.org/abs/1611.03280

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