Not signed in (Sign In)

Start a new discussion

Not signed in

Want to take part in these discussions? Sign in if you have an account, or apply for one below

  • Sign in using OpenID

Site Tag Cloud

2-category 2-category-theory abelian-categories accessible adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry bundles calculus categorical categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex complex-geometry computable-mathematics computer-science constructive cosmology deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration foundation foundations functional-analysis functor galois-theory gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck group group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory history homological homological-algebra homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory k-theory lie-theory limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monad monads monoidal monoidal-category-theory morphism motives motivic-cohomology newpage nlab noncommutative noncommutative-geometry number number-theory of operads operator operator-algebra order-theory pages pasting philosophy physics pro-object probability probability-theory quantization quantum quantum-field quantum-field-theory quantum-mechanics quantum-physics quantum-theory question representation representation-theory riemannian-geometry scheme schemes set set-theory sheaf simplicial space spin-geometry stable-homotopy-theory string string-theory superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory type type-theory universal variational-calculus

Vanilla 1.1.10 is a product of Lussumo. More Information: Documentation, Community Support.

Welcome to nForum
If you want to take part in these discussions either sign in now (if you have an account), apply for one now (if you don't).
    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeMay 25th 2010

    fianlly added the details of Dugger’s description of cofibrant objects in the projective model structure on simplicial presheaves in the section Cofibrant objects.

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeMay 25th 2010

    added more details on weak equivalences (local epimorphisms, really) in the Cech localization of the projective model structure from Dugger-Hollander-Isaksen

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJan 24th 2011
    • (edited Jan 24th 2011)

    at model structure on simplicial presheaves I have (finally) added a section

    Presentation of (oo,1)-toposes

    I have also added to the section Homtopy (co)limits the observation that finite homotopy limits in the local model structure may be computed in the global structure.

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeJan 24th 2011

    have added also a section Inclusion of chain complexes of sheaves, so far just observing the obvious Quillen adjunction induced from Dold-Kan

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeFeb 1st 2011
    • (edited Feb 1st 2011)

    I had had a section on descent for presheaves with coefficients in strict \infty-groupoids and how it relates to the descent of these regarded as simplicial presheaves over in the entry on smooth \infty-groupoids. Since it did not really belog there specifically at all, I have now moved that over to model structure on simplicial presheaves in a new section:

    Descent for values in strict and abelian \infty-groupoids.

    The main point is there a clear statement of Verity’s result of sufficient conditions under which Street’s definition of descent is actually correct and matches the one of simplicial presheaves.

    (I have only copy-and-pasted it for the moment. I should go through this and see if there is need to polish or otherwise improve this.)

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeMay 2nd 2018

    added pointer to the MO comment Garner 13 characterizing projectively cofibrant simplicial presheaves.

    Somebody should spell out the details here! If only by copy-and-pasting-and-beautifying-a-little the code from the MO answer.

    diff, v130, current

    • CommentRowNumber7.
    • CommentAuthorTim_Porter
    • CommentTimeMar 29th 2019

    Fixed some ?ech which should have been Čech.

    diff, v134, current

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeJul 7th 2020

    I have added publication data to

    diff, v137, current

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeJun 12th 2021
    • (edited Jun 12th 2021)

    cross-linked the discussion of local right properness (here) with locally cartesian closed model category and with locally cartesian closed (infinity,1)-category

    diff, v142, current

Add your comments
  • Please log in or leave your comment as a "guest post". If commenting as a "guest", please include your name in the message as a courtesy. Note: only certain categories allow guest posts.
  • To produce a hyperlink to an nLab entry, simply put double square brackets around its name, e.g. [[category]]. To use (La)TeX mathematics in your post, make sure Markdown+Itex is selected below and put your mathematics between dollar signs as usual. Only a subset of the usual TeX math commands are accepted: see here for a list.

  • (Help)