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The Wikipedia article about Acyclic models notices that the way that they were used in the proof of the Eilenberg–Zilber theorem laid the foundation stone to the idea of the model category.

Could somebody explain what exactly in the concept of acyclic models gave rise to considering/developing the concept of model category? What is precisely the core relation between the both concepts?

Recall that the intuition behind model categories is to "extract the essence" (e.g., containing certain distinguished classes of maps), which a category should intrinsically have in order to be "amenable" to constructing a homotopy theory from it.

The acyclic model is a subcategory $\mathcal{M} \subset \mathcal{K}$ which allows (if certain technical assumptions are satisfied) to develop a criterion when for two covariant functors $F,G: \mathcal{K} \to \operatorname{Comp}(R)$ (the latter is the category of complexes of $R$-modules for some ring $R$) and two natural transformations $f,g: F \to G$ there exists a chain homotopy between $f$ and $g$ presuming one "knows" what happens "in $0$-th layer", i.e., the zeroth homology of associated complexes which are "sufficiently well controlled" by restriction to $\mathcal{M}$. A kind of "lifting structure", which "knows" enough at $0$-layer about these functors $F$, $G$, to know about them at "all layers".

At least that's the rough idea how I understood the philosophy of acyclic models.
Now back to the question I posed at the beginning: In which way do acyclic models concretely motivate the idea behind a model category?

A naïve guess: Do the acyclic models $\mathcal{M} \subset \mathcal{K}$ in some sense or after appropriate modification provide archetypical examples of what later becomes axiomatically characterized as model category? If yes, can a model category be understood as attempt to axiomatize the "structural essence" of what structure an acyclic model should at least have, in order to have enough structure to be useful as an acyclic model for certain unspecified category $\mathcal{K}$ containing it?

Formulated in other words, could one say that $\mathcal{M}$ is a model category if and only if there exist a category $\mathcal{K}$ containing it, functors $F$, $G$ as above, such that $\mathcal{M}$ works as an acyclic model for it? (…just a naïve guess)?

Or in which other way does the idea of model categories arise from the concept of acyclic models?

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  • $\begingroup$ I think the wiki means that "this leads to the idea of the model category" (of chain complexes). (although I have no idea how that would be the case) $\endgroup$ Commented Sep 20, 2023 at 18:21
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    $\begingroup$ I read that more as "the proof of the E. Z. theorem using acyclic models lead to the idea of model categories", because it makes a lot more sense (using resolution and so on...) But I have no idea what are the evidence that justify this claim. $\endgroup$ Commented Sep 20, 2023 at 18:44
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    $\begingroup$ You know that you can see the history of who edited Wikipedia, right? Here it is for that page: en.wikipedia.org/w/…. The person who edited it to add that line (on Sept 3, 2016) does not appear to have expertise on model categories. You can see all contributions of that user including those around that date (en.wikipedia.org/w/index.php?title=Special:Contributions/…). Is seems they also added to the "model categories" entry a pointer to "acyclic models" and it was undone $\endgroup$ Commented Sep 20, 2023 at 21:00
  • $\begingroup$ @DavidWhite: So you suggest that there is no direct (historical) connection between these two concepts (at least up to now) known and the quoted statement is plainly wrong? $\endgroup$
    – user267839
    Commented Sep 20, 2023 at 22:40
  • $\begingroup$ I suggest it's possible that the statement is wrong. I'm unaware of any direct historical connection between the two, and we all know we should take things on wikipedia with a grain of salt. That's why I shared info about the person who updated it. $\endgroup$ Commented Sep 21, 2023 at 12:23

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