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arXiv · 2411.04102

Twisted tensor products: Alexander-Whitney and Eilenberg-Zilber maps

Anne V. Shepler·Sarah Witherspoon
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Abstract

Alexander-Whitney and Eilenberg-Zilber maps traditionally convert between the tensor product of standard resolutions and the standard resolution of a tensor product of algebras. We examine Alexander-Whitney and Eilenberg-Zilber maps for twisted tensor products, which include skew group algebras, smash products of Hopf algebras, Ore extensions, and universal enveloping algebras. These maps convert between the twist of standard resolutions and the standard resolution of a twist. We extend these to chain maps to and from twists of other resolutions. This allows one to transfer homological information between various resolutions of algebras and to expedite results on the deformation theory of twisted tensor product algebras.

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Anne V. Shepler, Sarah Witherspoon. 2024-11-06. Twisted tensor products: Alexander-Whitney and Eilenberg-Zilber maps. https://arxiv.org/abs/2411.04102

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