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    • to go with David C.’s recent edits

      v1, current

    • I worked on brushing up (infinity,1)-category a little

      • mostly I added in a section on homotopical categories, using some paragraphs from Andre Joyal's message to the CatTheory mailing list.

      • in this context I also rearranged the order of the subsections

      • I removed in the introduction the link to the page "Why (oo,1)-categories" and instead expanded the Idea section a bit.

      • added a paragraph to the beginning of the subsection on model categories

      • added the new Dugger/Spivak references on the relation between quasi-cats and SSet-cats (added that also to quasi-category and to relation between quasi-categories and simplicial categories)

    • added this pointer:

      • Andrew Kresch, On the geometry of Deligne-Mumford stacks (doi:10.5167/uzh-21342, pdf), in D. Abramovich, A. Bertram, L. Katzarkov, R. Pandharipande, M. Thaddeus (eds.) Algebraic Geometry: Seattle 2005, Proceedings of Symposia in Pure Mathematics Providence, Rhode Island: American Mathematical Society, 259-271 (pspum-80-1)

      Was looking for references to point readers to for background on the idea that DM-stacks and orbidfolds are essentially the same thing, realized in two different geometric categories (up to a list of inessential technical conditions). This is the best I have found so far. If anyone knows further references along these lines, please drop a note.

      diff, v14, current

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

      v1, current

    • added the statement (here) that Borel equivariant spectra are precisely the right induced genuine equivariant spectra

      diff, v3, current

    • I have added pdf-links to the reference

      and promoted this to the top of the list, since I suppose this is the most comprehensive account that a reader might want to go to first. Will also edit accordingly at topological stack

      diff, v18, current

    • I kept being annoyed about the nature of discussion of the “multiverse” (the one in cosmology, not the one in set theory). Now I thought instead of steadily being annoyed, I should start an nnLab entry that does it better. So I did now (or tried to), at multiverse.

    • Todd,

      you added to Yoneda lemma the sentence

      In brief, the principle is that the identity morphism id x:xxid_x: x \to x is the universal generalized element of xx. This simple principle is surprisingly pervasive throughout category theory.

      Maybe it would be good to expand on that. One might think that the universal property of a genralized element is that every other one factors through it uniquely. That this is true for the generalized element id xid_x is a tautological statement that does not need or imply the Yoneda lemma, it seems.

    • Adding my user page to the nLab. :)

      Nico Courts

      v1, current

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

      v1, current

    • starting something and need to save – nothing here yet

      v1, current

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

      v1, current

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

      v1, current

    • some minimum, just for completeness

      v1, current

    • added more references to 2-spectral triple (as far as I can see Jürg Fröhlich with his students was the first to try to formalize this to some extent)

    • felt like archiving a quote by Paul Taylor somewhere, it is now at folklore.

      Besides being funny, it is actually a useful comment for the newbie, and so I linked to it from category theory.

    • I noticed that augmented simplicial set did not point anywhere, so i created the entry. But have no energy to put anything of substance there right now.

    • to be !include-ed as a floating context menu into relevant entries

      v1, current

    • starting something, and need to save. nothing here yet, just a moment…

      v1, current