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arXiv · 1906.06228

Equivariant isomorphisms of Ext and Tor modules

Josh Pollitz
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Abstract

In this article we establish equivariant isomorphisms of Ext and Tor modules over different relative complete intersections. More precisely, for a commutative ring $Q$, this paper investigates how $Ext_{Q/(\boldsymbol{f})}^*(M,N)$ and $Tor^{Q/(\boldsymbol{f})}_*(M,N)$ change when one varies $\boldsymbol{f}$ among all Koszul-regular sequences of a fixed length such that $\boldsymbol{f} M=0$ and $\boldsymbol{f} N=0$. Of notable interest is how the theory of perturbations is used to establish isomorphisms of certain DG modules.

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Josh Pollitz. 2019-06-14. Equivariant isomorphisms of Ext and Tor modules. https://arxiv.org/abs/1906.06228

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