Simplicial and categorical comma categories

Constenoble, Steven R. (2001) Simplicial and categorical comma categories. Steven R. Costenoble.

Full text available as:

PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
202 Kb
Other (DVI File)
76 Kb


We consider four categories: the category of diagrams of small categories indexed by a given small category O, the (comma) category of small categories over O, the category of diagrams of simplicial sets indexed by O, and the category of simplicial sets over the nerve of O. Fritsch and Golasinski claimed that these four categories have equivalent homotopy categories but, in fact, their proof contains an error and the homotopy categories are not equivalent with the weak equivalences they use in the comma categories. We show here that the correct weak equivalences are the "weak fibre homotopy equivalences" defined by Latch. We also construct a model category structure on the category of simplicial sets over NO in which the weak equivalences are the weak fibre homotopy equivalences.

Item Type:Other
Uncontrolled Keywords:model categories simplicial sets diagrams comma categories
Subjects:Q Science > Q Science (General)
Q Science > QA Mathematics
ID Code:28
Deposited By:Admin HofPrints
Deposited On:03 January 2006

Repository Staff Only: edit this item