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    • Added to Klein geometry a section History with quotations for where exactly Klein actually speaks about G/HG/H.

      (This key passages is a bit hidden in Klein’s text, appearing at a somewhat unexpected point somewhere in the middle of a 35 page document.)

    • The entry on topological group could stand more work, but I added some stuff on the uniform structure, in particular the proposition that for group homomorphisms f:GHf: G \to H, continuity at a single point guarantees uniform continuity over all of GG. The proof is follow-your-nose, of course.

      What we really need is an entry Haar measure. I’ll get started on that soon.

    • Remove data that duplicates other pages, replacing with a disambiguation.

      diff, v9, current

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

      v1, current

    • mathematical physics with a slight distinction from physical mathematics which points to the same entry. The relation to theoretical physics has been discussed, but I am not sure yet if we should have theoretical physics as a separate entry so I do not put is as another redirect.

    • I edited three things: - In the definition of D XD_X I corrected what seems to be a typo : indeed D X([n])=X nD_X([n]) = X_n is a presheaf over SS, not a set (and then a simplicial presheaf, not a simplicial set)

      • In the definition of the notation [,][-,-] for simplicial presheaves, I edited the domain of that functor, which is not simply C:=SSet S opC:=SSet^{S^{op}}, but indeed C op×CC^{op}\times C

      • In the corollary that follows the introduction of D XD_X, I changed “evaluations of XX” into “evalutations of AA”, because in [X,A][X,A], we end up with holimlimA(U i)holim lim A(U_i)


      diff, v17, current

    • This is a definition of a category of filters.


      diff, v33, current

    • This is an article about the category of simplicial objects of the category of filters on sets, with a list of examples.


      v1, current

    • there is an old article (Berends-Gastman 75) that computes the 1-loop corrections due to perturbative quantum gravity to the anomalous magnetic moment of the electron and the muon. The result turns out to be independent of the choice of (“re”-)normalization (hence what they call “finite”).

      I have added a remark on this in the (g2)(g-2)-entry here and also at quantum gravity here.

    • Added the original paper by Whitney on fiber bundles.

      diff, v33, current

    • need to record some results on equivariant tubular neighbourhoods etc. Didn’t know where to put these, so I thought we’d need a dedicated entry on equivariant differential topology.

      v1, current

    • I guess it should read as “one defines the (Serre) quotient category A/TA/T as the one having the same objects as AA and ….” and not ” … same objects as TT… ” Similarily in the line following the line mentioned here.


      diff, v16, current

    • added

      • more hyperlinks (and some whitespace) to the paragraph on maximal tori.

      • the statement that smooth actions of compact Lie groups on smooth manifolds are proper

      diff, v9, current

    • just saw that rev 5, in an attempt to generalize away from Lie groups, left some incoherent logic in the text.

      I have tried to reorganize to make it work.

      diff, v14, current

    • I have changed the name to Haar Integral – if that’s ok – since the perspective I have added to the article leaves Haar measure as a consequence of Haar integral, and not the other way around.

      diff, v10, current

    • I have edited and rearranged just a little at normalizer, in order to clarify a little more.

    • brief category:reference entry on Bredon’s book, for ease of hyperlinking

      v1, current

    • tried to bring the entry Lie group a bit into shape: added plenty of sections and cross links to other nLab material. But there is still much that deserves to be done.

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

      v1, current

    • Fixed pdf link to “Towards an understanding of Girard’s transcendental syntax”


      diff, v6, current

    • I am giving this group a stub entry just to have a decent place to record today’s

      For this entry not to be all too lonely I made Spin(10,2) point to D=12 supergravity, for the moment. In the long run all this derserves to be expanded on, clearly.

      v1, current

    • After typing [[fixed point]]-spaces in various entries, I finally decided that “fixed point space” should have an entry of its own, with some comments and further pointers, if only for ease of hyperlinking.

      v1, current

    • Added a paragraph:

      In some papers, topological spaces are replaced by locales in the definition of étendues. For example, see Definition 1.1 in Rosenthal \cite{Rosenthal} or Definition 1.12 in Kock and Moerdijk \cite{KockMoerdijk}.

      diff, v25, current

    • Someone anonymous has raised the question of subdivision at cellular approximation theorem. I do not have a source here in which I can check this. Can anyone else check up?

    • Here’s a page untouched for a while – 2009. First person pronouns still being used.

      diff, v23, current

    • I have added at HomePage in the section Discussion a new sentence with a new link:

      If you do contribute to the nLab, you are strongly encouraged to similarly drop a short note there about what you have done – or maybe just about what you plan to do or even what you would like others to do. See Welcome to the nForum (nlabmeta) for more information.

      I had completly forgotton about that page Welcome to the nForum (nlabmeta). I re-doscivered it only after my recent related comment here.

    • Am making a start on trying to understand something of Mochizuki’s IUTT papers. I do not hold out any promises on how far I am going to get, or how long it is going to take me! Even this very first definition is going to me a long time, I think, as I intend to try to fill out all details. All help will be appreciated!

      v1, current