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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeDec 9th 2010
   • PermaLink
   Author: Urs
   Format: MarkdownItexedited [[model structure on sSet-presheaves]] a little

   edited model structure on sSet-presheaves a little

2. • CommentRowNumber2.
   • CommentAuthorHarry Gindi
   • CommentTimeDec 9th 2010
   • (edited Dec 9th 2010)
   • PermaLink
   Author: Harry Gindi
   Format: MarkdownItexHey Urs, do you know why they (Toen-Vezzosi) specifically used that model structure? It seems like it's a pretty annoying one to describe, and some other pages here show that it's Quillen equivalent to a bunch of much simpler ones.

   Hey Urs, do you know why they (Toen-Vezzosi) specifically used that model structure? It seems like it’s a pretty annoying one to describe, and some other pages here show that it’s Quillen equivalent to a bunch of much simpler ones.

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeDec 9th 2010
   • PermaLink
   Author: Urs
   Format: MarkdownItexHi Harry, i am not sure what you mean, could you expand? This is just the standard projective model structure on simplicial presheaves, set up in the enriched context.

   Hi Harry,

   i am not sure what you mean, could you expand? This is just the standard projective model structure on simplicial presheaves, set up in the enriched context.

4. • CommentRowNumber4.
   • CommentAuthorHarry Gindi
   • CommentTimeDec 9th 2010
   • PermaLink
   Author: Harry Gindi
   Format: MarkdownItexYes, but there are like 30 model structures on simplicial presheaves. This one (the local projective one) seems awfully complicated.

   Yes, but there are like 30 model structures on simplicial presheaves. This one (the local projective one) seems awfully complicated.

5. • CommentRowNumber5.
   • CommentAuthorUrs
   • CommentTimeDec 9th 2010
   • PermaLink
   Author: Urs
   Format: MarkdownItexI am still not sure what you mean. The porjective and injective model structures on simplicial presheaves are those that are easy to state. The intermediate model structures are more complicated. But they are almost never used (Jardine in his lectures points out a single article that uses an intermediate model structure).

   I am still not sure what you mean. The porjective and injective model structures on simplicial presheaves are those that are easy to state. The intermediate model structures are more complicated. But they are almost never used (Jardine in his lectures points out a single article that uses an intermediate model structure).

6. • CommentRowNumber6.
   • CommentAuthorHarry Gindi
   • CommentTimeDec 10th 2010
   • PermaLink
   Author: Harry Gindi
   Format: MarkdownItex@Urs: There is a global model on simplicial presheaves defined by objectwise fibrations and weak equivalences. This is the "global projective model structure". All of Toen's work (including his lecture notes on DAG and simplicial commutative rings, etc) use the local projective model structure (the one that also encodes descent and hypercovers and stuff).

   @Urs: There is a global model on simplicial presheaves defined by objectwise fibrations and weak equivalences. This is the “global projective model structure”. All of Toen’s work (including his lecture notes on DAG and simplicial commutative rings, etc) use the local projective model structure (the one that also encodes descent and hypercovers and stuff).