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arXiv · 1904.04965

A counterexample in quasi-category theory

Alexander Campbell
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Abstract

We give an example of a morphism of simplicial sets which is a monomorphism, bijective on 0-simplices, and a weak categorical equivalence, but which is not inner anodyne. This answers an open question of Joyal. Furthermore, we use this morphism to refute a plausible description of the class of fibrations in Joyal's model structure for quasi-categories.

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Alexander Campbell. 2019-04-10. A counterexample in quasi-category theory. https://doi.org/10.1090/proc%2F14692

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