160 reputation
18
bio website
location
age
visits member for 4 years, 11 months
seen 7 hours ago

7h
comment Cell(J) vs Cof(J) in $\text{sSet}_{\text{Quillen}}$
@Dmitri: yes thanks, I know this is true for cofibrations (see Hovey (1999) 3.2.2) but do you have a reference for the case of acyclic cofibrations or can you elaborate on it ?
1d
asked Cell(J) vs Cof(J) in $\text{sSet}_{\text{Quillen}}$
Nov
14
comment Fibrations of the injective model structure on G-simplicial sets
@SimonHenry: thanks for your answer, your construction of the diagonal filler is "pointwise" as I understand, so it's not clear for me that at the end you get a natural transformation compatible with the G-action.
Nov
6
comment Fibrations of the injective model structure on G-simplicial sets
@SimonHenry: do you have a reference for the characterization of the cofibrations you mentioned in the projective model structure ? Thanks.
May
6
comment Path objects in projective model structure
yes, I apologize for this ugly liberal use of LaTeX. Thanks David.
May
5
asked Path objects in projective model structure
Feb
3
revised intensional equality in type theory
deleted 7 characters in body; edited title
Jan
8
comment right adjoint for pullback along fibration
Thanks Ronnie for these helpful references, unfortunetly as I said in my previous comments I know this result and in particular this reference but my problem is to understand it. I must confess that I'm a bit lazzy and afraid by Giraud's paper which uses old notations.
Dec
21
comment right adjoint for pullback along fibration
For my part I read it, at least the statement is implicit, in Michael Shulman, Univalence For Inverse Diagrams p.10/11.
Dec
20
comment right adjoint for pullback along fibration
I know this is true because I read it somewhere without proof and so I'm looking for a proof.
Dec
20
comment right adjoint for pullback along fibration
No the existence is not part of the question. It's true however as you may know $Grpd$ is not locally cartesian closed. But along fibration this right adjoint exists, this is the point.
Dec
20
awarded  Commentator
Dec
20
comment right adjoint for pullback along fibration
It seems it's true but I was not able to find a demonstration. Especially it would be nice to have an explicit and elementary construction of this right adjoint even if I would be also grateful for a theorem that solves the question.
Dec
20
asked right adjoint for pullback along fibration
Dec
17
comment Model structure on stacks
Yes, I agree Fernando. And for my purpose (limits preserve cofibrations) that cofibrations are monomorphisms is just a sufficient condition but not needed.
Dec
16
comment Model structure on stacks
Correct me if I'm wrong but in jardine's model structure on simplicial presheaves cofibrations are the objectwise cofibrations and so are exactly the monomorphisms (since monos in sSet are objectwise monos ,ie injective maps, in Sets and sSet has pullbacks so monos in simplicial presheaves are exactly objectwise monos) so it can help.
Dec
16
comment Model structure on stacks
I don't know why my "Hi" at the beginning is deleted ?
Dec
16
asked Model structure on stacks
Nov
17
awarded  Notable Question
Oct
22
answered 2-sheaf definition in nlab