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arXiv · 2511.09849

$ω$-equifibrations between strict and weak $ω$-categories

Soichiro Fujii·Keisuke Hoshino·Yuki Maehara
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Abstract

We study $ω$-equifibrations between weak $ω$-categories in the sense of Batanin--Leinster. We define $ω$-equifibrations as a natural weak $ω$-categorical analogue of isofibrations between categories, and show that they can be characterised via the right lifting property with respect to a suitable set $J$ of strict $ω$-functors. The definition of $J$ involves the construction of a certain weak $ω$-category $\mathcal{E}^1$ which, roughly speaking, is freely generated by an equivalence 1-cell in a ``coherent'' manner. We show that the strict version of $\mathcal{E}^1$ coincides with Ozornova and Rovelli's coherent walking $ω$-equivalence $\widehat{ω\mathcal{E}}$. The $ω$-equifibrations between strict $ω$-categories coincide with the fibrations in the folk model structure.

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Soichiro Fujii, Keisuke Hoshino, Yuki Maehara. 2025-11-13. $ω$-equifibrations between strict and weak $ω$-categories. https://arxiv.org/abs/2511.09849

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