Metric enrichment, finite generation, and the path comonad

Alexandru Chirvasitu

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arXiv · 2205.12666

Metric enrichment, finite generation, and the path comonad

Alexandru Chirvasitu

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Abstract

We prove a number of results involving categories enriched over \textsc{CMet}, the category of complete metric spaces with possibly infinite distances. The category \textsc{CPMet} of intrinsic complete metric spaces is locally $\aleph_1$-presentable, closed monoidal, and comonadic over \textsc{CMet}. We also prove that the category \textsc{CCMet} of convex complete metric spaces is not closed monoidal and characterize the isometry-$\aleph_0$-generated objects in \textsc{CMet}, \textsc{CPMet} and \textsc{CCMet}, answering questions by Di Liberti and Rosick\'{y}. Other results include the automatic completeness of a colimit of bi-Lipschitz morphisms of complete metric spaces and a characterization of those pairs (metric space, unital $C^*$-algebra) that have a tensor product in the \textsc{CMet}-enriched category of unital $C^*$-algebras.

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Alexandru Chirvasitu. 2022-05-25. Metric enrichment, finite generation, and the path comonad. https://arxiv.org/abs/2205.12666

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