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arXiv · 2008.06257

Non-unital $C^{*}$-categories, (co)limits, crossed products and exactness

Ulrich Bunke
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Abstract

We provide a reference for basic categorial properties of the categories of (possibly non-unital) $\mathbb{C}$-linear $*$-categories or $C^{*}$-categories, and (not necessarily unit-preserving) functors. Generalizing the classical case of algebras with $G$-action, we extend the construction of crossed products to categories with $G$-action. We will show that the crossed product functor preserves exact sequences and excisive squares and sends weak equivalences to equivalences.

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Ulrich Bunke. 2020-08-14. Non-unital $C^{*}$-categories, (co)limits, crossed products and exactness. https://arxiv.org/abs/2008.06257

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