Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options answers only not deleted user 184

A model category is a category equipped with notions of weak equivalences, fibrations and cofibrations allowing to run arguments similar to those of classical homotopy theory.

73 votes

Do we still need model categories?

Here are some rough analogies: Model Category :: $(\infty, 1)$-category Basis :: Vector space Local coordinates :: Manifold I especially like the last one. When you do, say, differential geometry …
Chris Schommer-Pries's user avatar
49 votes

What are surprising examples of Model Categories?

The category of sets admits precisely nine model category structures, no more no less. I learned this fact from Tom Goodwillie's comments on a different MO question. It always shocks people when I m …
Chris Schommer-Pries's user avatar
16 votes
Accepted

Derived categories and homotopy categories

Yes. The former is a special case of the latter. There is a model category structure on the category of (say bounded) chain complexes of objects in your given abelian category. The weak equivalences a …
Chris Schommer-Pries's user avatar
11 votes
Accepted

Is the simplicial nerve a localization?

This is not true. Here is a counter example. We let $\mathcal{C}_*$ be the following simplicial category. It has two objects 0 and 1. Their only endomorphisms are the identity. There are no morphisms …
Chris Schommer-Pries's user avatar
4 votes
Accepted

Is a left Bousfield localization of simplicial presheaves a locally cartesian closed model c...

Section 2 of this paper of Rezk addresses exactly the question of when the localization by S yields a Cartesian model category. For that the relevant property is that that if you take the product of a …
Chris Schommer-Pries's user avatar