A counterexample in quasi-category theory

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)


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.
Original languageEnglish
Pages (from-to)37-40
Number of pages4
JournalProceedings of the American Mathematical Society
Issue number1
Early online date9 Jul 2019
Publication statusPublished - Jan 2020


  • inner anodyne
  • quasi-category
  • inner fibration
  • Weak factorisation system


Dive into the research topics of 'A counterexample in quasi-category theory'. Together they form a unique fingerprint.

Cite this