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    • Created a stub for this concept.

      v1, current

    • starting page on spatial σ\sigma-locales

      Anonymouse

      v1, current

    • starting page on sober σ\sigma-topological spaces

      Anonymouse

      v1, current

    • starting page on countably prime filters

      Anonymouse

      v1, current

    • starting page on linear orders / strict linear orders, which are pseudo-orders which satisfy linearity

      Anonymouse

      v1, current

    • have created geometric infinity-stack

      gave Toën’s definition in detail (quotient of a groupoid object in an (infinity,1)-category in TAlg opSpecSh (C)T Alg_\infty^{op} \stackrel{Spec}{\hookrightarrow}Sh_\infty(C) ) and indicated the possibility of another definition, along the lines that we are discussing on the nnCafé

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

      v1, current

    • stub entry, for the moment just to make the link work

      v1, current

    • added to quantum anomaly

      • an uncommented link to Liouville cocycle

      • a paragraph with the basic idea of fermioninc anomalies

      • the missing reference to Witten’s old article on spin structures and fermioninc anomalies.

      The entry is still way, way, stubby. But now a little bit less than a minute ago ;-

    • 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

    • category: people page for Jaap Fabius

      Anonymouse

      v1, current

    • category: people page for Juan Arias de Reyna

      Anonymouse

      v1, current

    • starting page on the Fabius function

      Anonymouse

      v1, current

    • starting page on bi-pointed sets

      Anonymouse

      v1, current

    • (Hi, I’m new)

      I added some examples relating too simple to be simple to the idea of unbiased definitions. The point is that we often define things to be simple whenever they are not a non-trivial (co)product of two objects, and we can extend this definition to cover the “to simple to be simple case” by removing the word “two”. The trivial object is often the empty (co)product. If we had been using an unbiased definition we would have automatically covered this case from the beginning.

      I also noticed that the page about the empty space referred to the naive definition of connectedness as being

      “a space is connected if it cannot be partitioned into disjoint nonempty open subsets”

      but this misses out the word “two” and so is accidentally giving the sophisticated definition! I’ve now corrected it to make it wrong (as it were).

    • 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

    • 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

    • 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.

    • 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