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    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • I have boosted the bibitems and clarified who did what (Anderson just states the structure, without proof. Bousfield just cites Anderson. Typing up the actual proof is due to Strickland.)

      diff, v12, current

    • New page, covering both French and English definitions, as well as limits of relations and spans, and restricted versions.

      v1, current

    • starting article on punctured neighborhoods

      Anonymouse

      v1, current

    • The entry test category which I wrote some time ago, came into the attention of Georges Maltsiniotis who kindly wrote me an email with a kind praise on nlab and noting that his Astérisque treatise on the topic of Grothendieck’s homotopy theory is available online on his web page and that the Cisinski’s volume is sort of a continuation of his Astérisque 301. Georges also suggested that we should emphasise that a big part of the Pursuing Stacks is devoted to the usage of test categories, so I included it into the bibliography and introductory sentence. I hinted to Georges that when unhappy with a state of an nlab entry he could just feel free to edit directly.

    • Made some improvements to connect the page to the rest of the nLab.

      diff, v2, current

    • stub – for the moment just as to satisfy links

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • I have created an entry type of types. Wanted to collect some literature there, but ended up not finding too much…

    • Page created, but author did not leave any comments.

      Anonymous

      v1, current

    • (definitely less than) bare minimum

      v1, current

    • added pointer to:

      • Albrecht Bertram, Stable Maps and Gromov-Witten Invariants, School and Conference on Intersection Theory and Moduli Trieste, 9-27 September 2002 (pdf)

      diff, v26, current

    • Proof was for soundness, not inconsistency.

      Anonymous

      diff, v2, current

    • Added link to Vaughan Pratt’s Linear Process Algebra.

      diff, v32, current

    • Cat in here says

      you can define Cat\Cat to be the 2-category of all UU'-small categories, where UU' is some Grothendieck universe containing UU. That way, you have SetCat\Set \in \Cat without contradiction.

      Do you agree with changing this to

      ” you can define Cat\Cat to be the 2-category of all UU'-small categories, where UU' is some Grothendieck universe containing UU. That way, for every small category JJ, you have the category Set J\Set^J an object of Cat\Cat without contradiction. This way, e.g. the diagram in Cat used in this definition of comma categories is defined. “

      ?

      Reason: motivation is to have the pullback-definition of a comma category in (For others, it’s about the diagram here) defined, or rather, having Cat provide a way to make it precise. Currently, the diagrammatic definition can either be read formally, as a device to encode the usual definition of comma categories, or a reader can try to consult Cat in order to make it precise. Then they will first find only the usual definition of Cat having small objects only, which does not take care of the large category

      Set ISet^I

      used in the pullback-definition. Then perhaps they will read all the way up to Grothendieck universes, but find that option not quite sufficient either since it only mentions Set, but not Set IntervalSet^{Interval} . It seems to me that large small-presheaf-categories such as Set IntervalSet^{Interval} can be accomodated, too, though.

      (Incidentally, tried to find a “canonical” thread for the article “Cat”, by using the search, but to no avail. Therefore started this one.)

    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • touched the formatting in congruence, fixed a typo on the cartesian square, added a basic example

    • Fixed a LaTeX typo in Remark 3.12. I’m not an expert so could someone double-check?

      diff, v141, current

    • Only a stub at the moment, but I thought we needed to start a page on this. Looks like it’s going to become important.

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • Created a stub for this concept.

      v1, current

    • Created a stub for cofunctor? with some references.

      v1, current

    • Just started and I’m called away, but I’ll save anyway.

      v1, current

    • am giving this its own entry, for ease of hyperlinking. Made up the terminology, maybe there is a better choice.

      v1, current

    • a stub entry, for the moment just so as to make some links work

      v1, current

    • Added:

      Specifically, a continuous functor CSetC\to Set is a right adjoint functor if and only if it is representable, in which case the left adjoint functor SetCSet\to C sends the singleton set to the representing object

      Related concepts

      diff, v3, current

    • a stub entry, for the moment just so that the link works

      v1, current

    • I added the remark that the canonical model structure on Cat is the model structure obtained by transferring the projective model structure on bisimplicial sets.