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    • In the definition, the article states "every object in C is a small object (which follows from 2 and 3)". The bracketed remark doesn't seem quite right to me, since neither 2 nor 3 talk about smallness of objects. Presumably this should better be phrased as in A.1.1 of HTT, "assuming 3, this is equivalent to the assertion that every object in S is small".

      Am I right? I don't (yet) feel confident enough with my category theory to change this single-handedly.

    • I added a little bit of material to ordered field, namely that a field is orderable iff it is a real field (i.e., −1-1 is not a sum of squares). More importantly, at real closed field, I have addressed an old query of Colin Tan:

      Colin: Is it true that real closure is an adjoint construction to the forgetful functor from real closed fields to orderable fields?

      by writing out a proof (under Properties) that indeed the forgetful functor from category of real closed fields and field homomorphisms to the category of real fields and field homomorphisms has a left adjoint (the real closure). Therefore I am removing this query from that page over to here.

    • I added to field a mention of some other constructive variants of the definition, with a couple more references.

    • concerning the discussion here: notice that an entry rig category had once been created, already.

    • Added a lemma about fully faithful functors.

      Sorry for the mess, there does not seem to be a way to preview edits.

      diff, v3, current

    • Domenico Fiorenza started a page for the thesis of his student, Alessandra Capotosti: From String structures to Spin structures on loop spaces.

      Am I right in thinking the main innovation is the passage from the map

      BSpin conn→B 2(BU(1) conn) \mathbf{B}Spin_{conn} \rightarrow {\mathbf{B}}^2({\mathbf{B}}U(1)_{conn})

      to

      BSpin→B 2(BU(1) conn)? \mathbf{B}Spin \rightarrow {\mathbf{B}}^2({\mathbf{B}}U(1)_{conn})?

      Is that likely to work more generally, e.g., can one do something similar with

      BString conn→B 7U(1) conn? \mathbf{B}String_{conn} \rightarrow {\mathbf{B}}^7 U(1)_{conn}?

    • added to supergravity Lie 6-algebra a brief discussion of how the equations of motion of 11-d supergravity encode precisely the “rheonomic” ∞\infty-connections with values in the supergravity Lie 6-algebra.

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

      v1, current

    • I worked on Nonabelian Algebraic Topology

      • made the entry “category: reference”. all about the book by Brown et al – if we feel we need a more generic entry with lower case title later, we can still split it off again

      • then I started adding a “Contents” section similar to what we have at Elephant and Higher Topos Theory etc., and started adding some of the content of relevance for the cosmic cube.

    • I have been editing the entry homotopy equivalence to include a brief discussion of strong homotopy equivalences and Vogt's lemma. In so doing, I have followed my nose and found various other entries to edit. For instance that for Hans Baues, that for cylinder functor, etc. I am thinking that the general area of Henry Whitehead's idea of algebraic homotopy, may be a useful intermediate one between the infinity category ideas (which could be seen as just a 'souped up' version of Kan complexes), (I am not saying they are just that a cynic might make them out to be!) and the algebraic topologists desire to perform calculations. Note the quotes at algebraic homotopy. Of course, they d not say what 'compute' means in this context. (Note we do not have an entry on Whitehead as yet.)

    • Fixed a broken link to Jardine’s lectures.

      This article references Jardine’s lectures for a cubical subdivision functor, but I could not find it in this source. Is cubical subdivision described elsewhere?

      diff, v4, current

    • For no particular reason, I have added another illustrating graphics to the entry, taken from Fig 1.3 in Apostol 1973.

      diff, v19, current

    • A comparatively long and technical section “From hom-functors to units and counits” (on adjoint functors) was sitting inside the Idea-section of adjunction. It seemed plainly misplaced there, and distracting attention from what should be the content of this entry, as opposed to the entry adjoint functor. So I have moved it now to where it seems to belong: inside the Examples-section.

      diff, v55, 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

    • brief category:people-entry for hyperlinking references

      v1, current

    • too lazy to make full page but a quick definition is better than nothing

      4u9ust

      v1, current

    • subdivided the Properties-section into subsections; added subsection for branched coverings of nn-spheres

      diff, v39, current

    • tried to polish one-point compactification. I think in the process I actually corrected it, too. Please somebody have a close look.

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

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • When pointing somebody to it, I noticed that the entry n-category is in a rather sad state and in particular it used to start out in a rather unhelpful fashion. I have now tried to briefly fix at least the latter problem by expanding and editing the first two sentences a bit. Notably I made sure that a pointer to (∞,n)-category appears early on, for that is a place with more robust information, currently.

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