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

• (I’m currently reading through Keller’s book Differential Calculus in Locally Convex Spaces.)

• created product law, since I wanted to be able to link to it…

• added to KK-theory brief remark and reference to relation to stable $\infty$-categories / triangulated categories

• Created the page unbounded topos, and some links at topos and bounded geometric morphism.

I’m interested in the generalisation of the construction of the unbounded topos $\mathrm{Gl}\left(F\right)$ to the general case of an inaccessible comonad $G$ on a bounded topos (which wlog we might as well take to be $\mathrm{Set}$ EDIT: NO, LET’S NOT). In essence, why is it unbounded? Also, what nice properties can we claim of the category of coalgebras for $G$, given information about $G$.

Note also, the paper HOW LARGE ARE LEFT EXACT FUNCTORS? in TAC in 2001 seems to claim something a little stronger than Johnstone does in the Elephant, and recounted at topos, namely that the existence of lex endofunctors of set is independent of ZFC (they say something more general, but it covers this case). This is mostly a note to myself, but if others feel like looking, that would be good too.

• There is discussion about material and structural set theories at set theory, spilt over from the Café.

• I gave index an Idea-section.

In the course of this I created some stubby auxiliary entries, such as (in rapidly increasing order of stubbieness)

• Someone has made a change to the page on Aleksandr Aleksandrov, but there are some characters in the Cyrillic form of his name that are not coming out. Does anyone know how to fix this?

• You may have seen in “Recently revised” that I had edited 11-dimensional supergravity in the last days. I wanted to start a section there on the details of the action functional. But after adding some formulas, I ran out of time and just left an “under construction”-warning.

The reason I ran out of time is that I had to first write related things with higher priority into an article we are currently preparing:

Later when the dust has settled and I have more leisure, I’ll try to take care of the $n$Lab’s 11d sugra article again.

• started Fierz identity to collect some references. Am still searching for the good reference for the general case…

• made Ben Webster’s recent observation the Idea-section at Hall algebra (see the link given there)

• 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)

• wrote something at cosmic string and by copy-and-pasting-and-changing-the-degrees added something similar to domain wall and monopole. Needs a bit more polishing, maybe.

I am really working on writing out an abstract re-formulation of this classical theory in terms of extended TQFT with defects, but not done with that yet (and will probably be interrupted again before finishing it).