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arXiv · 2203.07174

Cohomological supports of tensor products of modules over commutative rings

Srikanth B. Iyengar·Josh Pollitz·William T. Sanders
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Abstract

This works concerns cohomological support varieties of modules over commutative local rings. The main result is that the support of a derived tensor product of a pair of differential graded modules over a Koszul complex is the join of the supports of the modules. This generalizes, and gives another proof of, a result of Dao and the third author dealing with Tor-independent modules over complete intersection rings. The result for Koszul complexes has a broader applicability, including to exterior algebras over local rings.

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Srikanth B. Iyengar, Josh Pollitz, William T. Sanders. 2022-03-14. Cohomological supports of tensor products of modules over commutative rings. https://arxiv.org/abs/2203.07174

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