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arXiv · 2401.11781

Kleisli categories, T-categories and internal categories

Dominique Bourn
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Abstract

We investigate the properties of the Kleisli category KlT of a monad (T,{\lambda},{\mu}) on a category E and in particular the existence of (some kind of) pullbacks. This culminates when the monad is cartesian. In this case, we show that any T-category in E in the sense of A. Burroni coincides with a special kind of internal category in KlT . So, it is the case in particular for T -operads and T -multicategories. More unexpectedly, this, in turn, sheds new lights on internal categories and n-categories.

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Dominique Bourn. 2024-01-22. Kleisli categories, T-categories and internal categories. https://arxiv.org/abs/2401.11781

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