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arXiv · 2308.01103

Improved Kunneth Tricks

Amnon Yekutieli
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Abstract

The Kunneth trick is a formula for the top cohomology of the derived tensor product of two complexes of modules over a ring. In this note we present two improvements of this formula. The first improved Kunneth trick is a formula for the top cohomology of the plain tensor product of two DG modules over a nonpositive DG ring. The second trick handles the derived tensor product of two DG modules over a nonpositive DG ring. The proofs are elementary.

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Amnon Yekutieli. 2023-08-02. Improved Kunneth Tricks. https://arxiv.org/abs/2308.01103

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