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

• New entry observable wanted at many entries. For now the very basic stuff, with a view toward maximal generality.

• I have put a copy of my thesis, as it is being handed up for examination, on my personal web.

David Roberts
• combinatorics

Maybe some could be interested in reviewing it (Toby?).

• I added some comments to Trimble n-category regarding a coinductive way to state the definition, which I think is very clean and neat, and also a little mind-blowing.

• expanded the previously pretty empty entry smooth Lorentzian space.

I added some standard definitions for smooth Lorentzian manifolds and then a discussion on how a time orientation without closed future-directed curves induces the structure of a category that is a poset, where a morphism $x \to y$ witnesses the fact that $y$ is a point in the future of $x$.

• As per someone's suggestion, I am going to do what Zoran does and have one, continuously running forum topic with my latest changes.

My latest change: added response to Zoran's query at quantum mechanics.
• While Prof. Joyal in his joyalscatlab keeps the lists of contributors to category theory and to homological algebra, I thought it might be useful to have some complementary list for 2-3 other fields in our nlab. But this could be too much work. So I restrained with contributors to algebraic geometry, as over 20 are alerady present in the nlab anyway (algebraic geometry has much being intertwined with the development of category theory since Serre and Grothendieck). Created Jean-Pierre Serre and Shigeru Mukai, wanted also at the Timeline entry; and David Mumford. This entry should be useful as we do not have top entry of contents for alegbraic geometry. (and I do not plan it soon).

• created floating toc quasi-category theory contents

there is still a lot left to type in concerning quasi-category theory, but it seemed to me about time to collect what is there and organize it, so that one can see what we have, what is missing, and so that readers find their way to their information

• some Anonymous Coward added an unmotivated link to some web-hosting site at factorization algebra. I have rolled back the entry to before that edit.

I am wondering if the creatures who do such things wiill at least eventually learn something from reading about things like factorization algebras...

• We should have an entry on large N limit gradually. But sometimes it can be treated as a semiclassical limit. I quoted a reference by Yaffe where I originally read of that approach to the entry semiclassical expansion.

• I have been greatly expanding the entry generalized multicategory, to work up gradually from the most explicit and easy-to-understand Leinster definition through profunctors, double categories, and up to the most general situation considered in my paper with Geoff, with examples. There's lots more left to do, but I have to run to a seminar now.

• I fixed up an obvious error in a claim at Dold fibration: the counterexample there showed the converse of what was claimed (and I think the error was due to me). Now I'd like to find a proper counterexample, so I'll ask on MathOverflow, in case anyone has one up their sleeve.

• I began working on a page for the GNS construction but started dozing off at my keyboard (so it needs someone to help finish it). Also I added a note on QBism and category theory to the page on quantum states. In it I assert that category theory is, in essence, a theory about relations (bear with me on this one - read the entry).
• Started monoidal bicategory with a bunch of references to the tortuous literature on braided and symmetric things. Please correct me if I left anything out. It would be nice to have the "accepted/correct" definitions here eventually, for reference.

• Didn't have much free time, but managed to add a little bit to Stokes phenomenon and responded to Zoran's query about Birkhoff's theorem. I suggested we rename it "Birkhoff-von Neumann theorem" so as not to confuse it with other similarly titled theorems.
• I have started an entry on group presentations. This will lead to a discussion of identities among relations as well as feeding into the rewriting page.

• edited decalage a bit

there was the statement that $Dec Y \to Y$ is a "fibration". I made that Kan fibration. Is that right?