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arXiv · 1601.07826

Cuntz-Pimsner Algebras and Twisted Tensor Products

Adam Morgan
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Abstract

Given two correspondences $X$ and $Y$ and a discrete group $G$ which acts on $X$ and coacts on $Y$, one can define a twisted tensor product $X\boxtimes Y$ which simultaneously generalizes ordinary tensor products and crossed products by group actions and coactions. We show that, under suitable conditions, the Cuntz-Pimsner algebra of this product, $\mathcal O_{X\boxtimes Y}$, is isomorphic to a "balanced" twisted tensor product $\mathcal O_X\boxtimes_\mathbb T\mathcal O_Y$ of the Cuntz-Pimsner algebras of the original correspondences. We interpret this result in several contexts and connect it to existing results on Cuntz-Pimsner algebras of crossed products and tensor products.

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Adam Morgan. 2016-01-28. Cuntz-Pimsner Algebras and Twisted Tensor Products. https://arxiv.org/abs/1601.07826

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