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Jun 10, 2021 at 9:39 comment added Fernando Muro Excellent point @UrsSchreiber No, I don't know of any reference but it looks like something interesting to look at. I actually remember someone rising this question last time I talked about derivators a couple of years ago, in person.
Jun 10, 2021 at 7:26 comment added Urs Schreiber @FernandoMuro I think your pointer to Renaudin's result ncatlab.org/nlab/show/Ho(CombModCat) is the most pertinent reply here, since the only way to really know how derivators relate to ∞-categories is to compare the (large) categories (n-categories) which both form. The only trouble is that your comment takes for granted a fact whose proof seems to be sadly missing in the literature: That the 2-category of combinatorial model categories localized at Quillen equivalences is equivalent to the homotopy 2-category of presentable ∞-categories. This ought to be true, but is there a proof?
S Aug 3, 2020 at 3:18 history bounty ended Amos Kaminski
S Aug 3, 2020 at 3:18 history notice removed Amos Kaminski
Aug 1, 2020 at 17:58 vote accept Amos Kaminski
Jul 30, 2020 at 11:34 comment added Fernando Muro My second comment is kind of infamous, one has to put a lot of will to understand it well, I'm tempted to erase it.
Jul 30, 2020 at 11:31 comment added Fernando Muro @mikeshulman I actually said "very roughly" ;) thanks for stressing this part, it's difficult to sum up, better to look at the reference, which doesn't even talk about infinity categories!
Jul 30, 2020 at 11:29 comment added Mike Shulman It took me a while to figure out what you meant by "derivators are to ∞-categories what homotopy theory is to topology". Would a more precise version of the statement end with "...what 𝛱-algebras are to spaces"?
Jul 30, 2020 at 11:22 comment added Mike Shulman @FernandoMuro Your statement is missing the very important adjective "locally presentable" in front of "derivators" and "$(\infty,1)$-categories". (I know you said "roughly speaking", but I think this is important not to omit. For one thing, a derivator is always complete and cocomplete, whereas an arbitrary $(\infty,1)$-category is not!)
Jul 29, 2020 at 18:04 comment added Fernando Muro So, yes, you miss information but you do keep a lot. Also, very roughly speaking (and shifting dimensions by $-1$), derivators are to $\infty$-categories what homotopy theory is to topology. So, if you like homotopy theory, probably you should also like derivators as much.
Jul 29, 2020 at 18:01 comment added Fernando Muro Very roughly speaking, by [Ren09] the $2$-category of derivators is equivalent to: 1. Take the $(\infty,1)$-category of $(\infty,1)$-categories. 2. Truncate it to a $(2,1)$-category. 3. Perform a $2$-categorical localization inverting those $1$-morphisms which induce an equivalence on homotopy categories. [Ren09] Renaudin, Olivier. 2009. “Plongement de Certaines Théories Homotopiques de Quillen Dans Les Dérivateurs.” Journal of Pure and Applied Algebra 213 (10): 1916–1935. doi.org/10.1016/j.jpaa.2009.02.014.
Jul 29, 2020 at 17:37 answer added Mike Shulman timeline score: 26
S Jul 29, 2020 at 12:20 history bounty started Amos Kaminski
S Jul 29, 2020 at 12:20 history notice added Amos Kaminski Draw attention
Jul 29, 2020 at 9:20 comment added Mirco A. Mannucci Deleted my answer. Now, Kevin, Harry and Mike, I would be very interested in reading your answers here.
Jul 28, 2020 at 6:33 comment added Kevin Carlson I don't know that I have a really compelling answer here, but to Denis and Lennart's points the answer is: at best only in terms of homotopy limits in a model structure, which is a major advantage of $\infty$-categories. Derivators are better suited to working within a single homotopy theory at a time. Regarding your second question, well, since Lurie began writing there has been vastly more machinery developed for $\infty$-categories, and some things (see above) have been done only in that framework.
Jul 27, 2020 at 17:46 comment added Denis Nardin Another version of Lennart's comment: can you talk about sheaves of derivators? One of the great strenghts of ∞-cats is that they work very well in families (so, for example, you can rephrase faithfully flat descent as "$\mathrm{QCoh}(-)$ is a sheaf")
Jul 27, 2020 at 17:19 history edited Amos Kaminski CC BY-SA 4.0
added 20 characters in body
Jul 27, 2020 at 16:59 comment added Fernando Muro The following paper shows interesting relations between both: Arlin, Kevin. 2020. “On the $\infty$-Categorical Whitehead Theorem and the Embedding of Quasicategories in Prederivators.” ArXiv:1612.06980 [Math], February. arxiv.org/abs/1612.06980.
Jul 27, 2020 at 11:11 comment added Lennart Meier Can one take a limit of a diagram of derivators?
Jul 27, 2020 at 9:56 history edited David Roberts CC BY-SA 4.0
Grammar and tags
Jul 27, 2020 at 9:10 history asked Amos Kaminski CC BY-SA 4.0