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    • following discussion here I am starting an entry with a bare list of references (sub-sectioned), to be !include-ed into the References sections of relevant entries (mainly at homotopy theory and at algebraic topology) for ease of updating and syncing these lists.

      The organization of the subsections and their items here needs work, this is just a start. Let’s work on it.

      I’ll just check now that I have all items copied, and then I will !include this entry here into homotopy theory and algebraic topology. It may best be viewed withing these entries, because there – but not here – will there be a table of contents showing the subsections here.

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • starting page on author

      Anonymouse

      v1, current

    • I’m making a correction about enriched vs internal categories.

      An algebroid is a category enriched in Vect, according to the nLab page on algebroids. Meanwhile, a category internal to Vect is what Baez and Crans call a “2-vector space”.

      diff, v18, current

    • added disambiguation with the notion in probability theory

      diff, v3, current

    • starting page on mutually exclusive events in probability theory

      Anonymouse

      v1, current

    • starting disambiguation page on mutual exclusivity

      Anonymouse

      v1, current

    • starting page on mutual exclusivity

      Anonymoue

      v1, current

    • starting page on the law of non-contradiction

      Anonymouse

      v1, current

    • starting disambiguation page for inequality

      Anonymous

      v1, current

    • added table of contents and section headers to the article

      Anonymouse

      diff, v6, current

    • starting page on the type of affine propositions in the antithesis interpretation

      Anonymouse

      v1, current

    • Added reference to Bruce Bartlett’s thesis.

      diff, v5, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • Added several classical books on complex analytic spaces

      Anonymous

      diff, v11, current

    • Created the page and added some references

      v1, current

    • I added to excluded middle a discussion of the constructive proof of double-negated LEM and how it is a sort of “continuation-passing” transform.

    • I’ve been inactive here for some months now; I hope this will significantly change soon.

      I have written a stubby beginning of iterated monoidal category, with what is admittedly a conjectural definition that aims to be slick. I am curious whether anyone can help me with the following questions:

      • Is the definition correct (i.e., does it unpack to the usual definition)? If so, is there a good reference for that fact?

      • Assuming the definition is correct, it hinges on the notion of normal lax homomorphism (between pseudomonoids in a 2-category with 2-products). Why the normality?

      In other words (again assuming throughout that the definition is correct), it would seem natural to consider the following type of iteration. Start with any 2-category with 2-products CC, and form a new 2-category with 2-products Mon(C)Mon(C) whose 0-cells are pseudomonoids in CC, whose 1-cells are lax homomorphisms (with no normality condition, viz. the condition that the lax constraint connecting the units is an isomorphism), and whose 2-cells are lax transformations between lax homomorphisms. Then iterate Mon()Mon(-), starting with C=CatC = Cat. Why isn’t this the “right” notion of iterated monoidal category, or in other words, why do Balteanu, Fiedorowicz, Schwänzel, and Vogt in essence replace Mon()Mon(-) with Mon norm()Mon_{norm}(-) (where all the units are forced to coincide up to isomorphism)?

      Apologies if these are naive questions; I am not very familiar with the literature.

    • I think the line between the two types of Kan extension (weak versus pointwise) is drawn at the wrong place. Am I missing something?

    • Added list of low dimensional manifolds and removed them from the example section.

      diff, v17, current

    • creating a stub entry, for now just to make the link work, and to have a home for references specific to abelian CS

      v1, current

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

      Anonymous

      v1, current

    • http://ncatlab.org/nlab/show/Isbell+duality

      Suggests that Stone, Gelfand, … duality are special cases of the adjunction between CoPresheaves and Presheaves. A similar question is raised here. http://mathoverflow.net/questions/84641/theme-of-isbell-duality

      However, this paper http://www.emis.ams.org/journals/TAC/volumes/20/15/20-15.pdf

      seems to use another definition. Could someone please clarify?

    • added to G2 the definition of G 2G_2 as the subgroup of GL(7)GL(7) that preserves the associative 3-form.

    • I began to add a definition of conformal field theory using the Wightman resp. Osterwalder-Schrader axiomatic approach. My intention is to define and explain the most common concepts that appear again and again in the physics literature, but are rarely defined, like “primary field” or “operator product expansion”.

      (I remember that I asked myself, when I first saw an operator product expansion, if the existence of one is an axiom or a theorem, I don’t remember reading or hearing an answer of that until I looked in the book by Schottenloher).

    • starting something, but nothing much here yet

      v1, current

    • Fix naming of index variable to match index on expression inside.

      Greg Langmead

      diff, v3, current

    • Added to noetherian ring a homological chacaterization: a ring is Noetherian iff arbitrary direct sums of injective modules are injective.

    • Added more lowbrow, quicker-to-understand definition of “coherent ring”.

      diff, v3, current

    • starting page on 𝒜\mathcal{A}-rings

      Anonymouse

      v1, current

    • I have spelled out the proofs that over a paracompact Hausdorff space every vector sub-bundle is a direct summand, and that over a compact Hausdorff space every topological vector bundle is a direct summand of a trivial bundle, here

    • starting page on 𝒜\mathcal{A}-groups

      Anonymouse

      v1, current

    • starting page on 𝒜\mathcal{A}-monoids

      Anonymouse

      v1, current

    • starting page on the cartesian product of 𝒜\mathcal{A}-sets

      Anonymouse

      v1, current

    • starting page on the tensor product of 𝒜\mathcal{A}-sets

      Anonymouse

      v1, current

    • starting page on affine sets

      Anonymouse

      v1, current

    • starting a disambiguation page on affine functions

      Anonymouse

      v1, current

    • Added appropriate axioms for the various definitions of affine space, along with another definition in terms of a single quaternary operation.

    • starting page on affine functions in the antithesis interpretation of constructive mathematics

      Anonymouse

      v1, current

    • Unfortunately, there are two entries on the same topic, both created by Urs: quantum Hall effect (redirecting also fractional quantum Hall effect what should eventually split off) with some substance, and the microstub quantum hall effect. I would like to create quantum spin Hall effect and I think I should rename/reclaim the stub quantum hall effect for this. Do others agree ? Urs ?

      As the action is now delayed I record here the reference which I wanted to put there

      • B. Andrei Bernevig, Taylor L. Hughes, Shou-Cheng Zhang, Quantum spin Hall rffect and topological phase transition in HgTe quantum wells, Science 15 December 2006: 314, n. 5806, pp. 1757-1761 doi

      Somewhat surprisingly, the authors and roughly this work of them are mentioned (though not in the list of references) in a paper in algebraic geometry

      which considers the mirror symmetry and topological states of matters (topological insulators in particular) as main applications.

    • starting page on obtuse triangles

      Anonymouse

      v1, current

    • starting page on right triangles since the paper

      • John Baez, The Moduli Space of Acute Triangles, Notices of the American Mathematical Society, Volume 71, Number 5, pages 664-665, May 2024. (arXiv:2407.06201, pdf)

      talks about right triangles too

      Anonymouse

      v1, current

    • Deleted from the History section three consecutive paragraphs begining with “More precisely, when a moduli space…” that appeared in verbatim copy in the Idea section.

      diff, v33, current

    • Adding reference

      • John Baez, The Moduli Space of Acute Triangles, Notices of the American Mathematical Society, Volume 71, Number 5, pages 664-665, May 2024. (arXiv:2407.06201, pdf)

      Anonymouse

      diff, v22, current

    • I have expanded vertex operator algebra (more references, more items in the Properties-section) in partial support to a TP.SE answer that I posted here