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Nov 10, 2022 at 8:59 vote accept Gabriel
Nov 9, 2022 at 21:50 comment added Zhen Lin FWIW these comments also apply to isofibrations of ordinary categories. They are technically convenient and allow us to strictify.
Nov 9, 2022 at 20:06 comment added Kevin Carlson @ManuelAraújo Just to clarify, the isofibrations aren't precisely the fibrations in the Joyal model structure. But every fibration is an isofibration, and every isofibration between quasicategories is a fibration, so in the $\infty$-cosmos context (where every object is fibrant) the more mysterious Joyal fibrations can be ignored.
Nov 9, 2022 at 20:03 answer added Kevin Carlson timeline score: 7
Nov 9, 2022 at 9:22 comment added Manuel Araújo I am also not an expert (hence the comment instead of an answer), but here is an example. Say you want to to compute a homotopy pullback of a diagram of spaces. If one of the maps involved is a fibration, you can just take the strict pullback of the diagram.
Nov 9, 2022 at 9:07 comment added Gabriel Dear @ManuelAraújo, would you mind explaining a little why this fact allow them work with 2-categories instead of bicategories? (I also know very little about model categories, but I would appreciate any explanation.)
Nov 9, 2022 at 8:56 comment added Manuel Araújo They are the fibrations in the Joyal model structure on simplicial sets, whose fibrant objects are quasicategories. This means in particular they achieve what is stated in the Introduction: "To help us achieve this counterintuitive strictness, each ∞-cosmos comes with a specified class of maps between ∞-categories called isofibrations. The isofibrations have no homotopy-theoretic meaning, as any functor between ∞-categories is equivalent to an isofibration with the same codomain".
Nov 9, 2022 at 8:38 history asked Gabriel CC BY-SA 4.0