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arXiv · 1804.08710

Accessibility and presentability in 2-categories

Ivan Di Liberti·Fosco Loregian
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Abstract

We outline a definition of accessible and presentable objects in a 2-category $\mathcal K$ endowed with a "KZ context", that is to say a pair of lax-idempotent monads interacting in a prescribed way; this perspective suggests a unified treatment of many "Gabriel-Ulmer like" theorems, asserting how presentable objects arise as reflections of generating ones. We outline the notion of "(Gabriel-Ulmer) envelope" for a KZ context, sufficient to concoct Gabriel-Ulmer duality. We end the paper with a roundup of examples, involving classical (set-based and enriched), low dimensional category theory, and a perspective for future work, rooted in higher category theory and homotopy theory.

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Ivan Di Liberti, Fosco Loregian. 2018-04-23. Accessibility and presentability in 2-categories. https://doi.org/10.1016/j.jpaa.2022.107155

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