Edge Rewrite
// HTMLRewriter · presentation

This page was redesigned at the edge.

Cloudflare fetched the original article and streamed it through HTMLRewriter to apply an entirely new visual system without rebuilding the source page.

// request.cf · coarse context

A page that knows where it met you.

Only coarse request metadata is shown. This demo does not display or persist visitor IP addresses.

Country
US
Cloudflare location
CMH
Connection
HTTP/2
Language
Not provided

Ray ID: a229aae04ad379f3

Jump to content

Talk:Homotopy category

Page contents not supported in other languages.
Add topic
From Wikipedia, the free encyclopedia
Latest comment: 17 years ago by 69.204.54.113 in topic Homotopy categories of model categories.

Homotopy categories of model categories.

[edit]

It seems to me that this description of a homotopy category is too narrow. From the current perspective homotopy categories are usually understood in the context of model categories. For a model category M its homotopy category is equivalent to the category constructed by taking the full subcategory of M on fibrant-cofibrant objects and then inverting all weak equivalences. As a result one does not need to argue which homotopy category is "the" homotopy category - there is one for each model category. One ("Serre") model category structure on the category of topological spaces yields the homotopy category equivalent to the category of CW-complexes and homotopy classes of maps between CW-complexes. Another ("Hurewicz") model category structure on topological spaces produces the homotopy category equivalent to the category of all spaces with homotopy classes of maps as morphisms. --69.204.54.113 (talk) 05:27, 22 August 2008 (UTC)Reply

Assessment comment

[edit]

The comment(s) below were originally left at Talk:Homotopy category/CommentsTalk:Homotopy category/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

* First of all, this article has no references. It also presents as rather stream-of-consciousness, with neither an introductory overview nor a conceptual flow. The context given is mainly of interest to specialists, and the information comes off as having been chosen haphazardly. It could be either a weak "Start" or a strong "Stub", but I think it needs a lot of reorganization, expansion, and polishing. Ryan Reich 01:35, 6 July 2007 (UTC)Reply

Last edited at 01:35, 6 July 2007 (UTC). Substituted at 02:13, 5 May 2016 (UTC)