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    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • I found the definition of a scheme to be slightly unclear/insufficiently precise at one point, so I have tweaked things slightly, and added more details. Indeed, it is quite common to find a formulation similar to ’every point has an open neighbourhood isomorphic to an affine scheme’, whereas I think it important to be clear that one does not have the freedom to choose the sheaf of rings on the local neighbourhood, it must be the restriction of the structure sheaf on XX.

      diff, v30, current

    • Auke Booij’s thesis Analysis in univalent type theory as well as the HoTT book explicitly defines an ordered field to have an lattice structure on the underlying commutative ring, which is different from the definition of an ordered field in the nlab article, where such a condition is missing. (by lattice I mean unbounded lattice, or what some people call pseudolattices)

      However, there are no references in the current nlab article on ordered fields showing that an ordered field doesn’t have a lattice structure in constructive mathematics. The basic definition lacking a lattice structure was already written in 2010 in the first revision of the article by Toby Bartels, and the other editors of the article, Todd Trimble and a few anonymous editors from earlier this year, all accepted the basic definition provided by Toby Bartels, since it hasn’t been modified since the first revision. So if they are still around I would like them or somebody else to provide references from the mathematical literature justifying that ordered fields do not necessarily have a lattice structure, or prove that every ordered field as currently defined has a compatible lattice structure. Otherwise I’ll insert the lattice structure into the definition.

    • brief category:people-entry for hyperlinking references

      v1, current

    • Clarify that the impredicative definition only quantifies over truth values.

      diff, v18, current

    • I am working on the entry supergravity C-field. On the one hand I am in the process of adding in more on the DFM model. On the other I am describing how to reformulate aspects of this in terms of infinity-Chern-Weil theory (this with Domenico Fiorenza and Hisham Sati behind the scenes).

      Not done yet, so beware.

    • For now creating page, content to be added soon.

      v1, current

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

    • New article mostly clarifying definitions of ’semidefinite integral’ vs ’indefinite integral’ vs ’antiderivative’.

      v1, current

    • I want this entry to have an actual section on construction of (compact) Examples, so I started one (here). But so far there is nothing in there apart from pointers to the original articles by Joyce and Kovalev, and a graphics illustrating Kovalev’s twisted connected sums.

      diff, v51, current

    • For now creating page, content to be added soon.

      v1, current

    • For now creating page, content to be added soon.

      v1, current

    • For now creating page, more to be added soon.

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

      • T.T. Wu, C. N. Yang, Dirac monopole without strings: monopole harmonics, Nuclear Physics B107:3 (1976) 365–380

      diff, v7, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • starting something – not done yet

      v1, current

    • example of nominal sets with separated tensor added, see Chapter 3.4 of Pitts monograph Nominal Sets

      Alexander Kurz

      diff, v21, current

    • I create this page to describe precisely the theorem Thomas Fox is known for.

      v1, current

    • For some time now I’ve been bothered by an implicit redundancy spanned by the articles nice category of spaces and convenient category of topological spaces. I would like the latter to have a more precise meaning and the former to be something more vague and flexible. I have therefore been doing some rewriting at the former. But if anyone disagrees with the edits, please let’s discuss this here.

      I have removed a query box:

      +– {: .query} I’m not sure that we really want to use the terminology that way, but Ronnie already created that page, so I’m linking these together. —Toby =–

    • a stub entry, for the moment just to record some references

      v1, current

    • updated link to Charles Rezk paper

      Anonymouse

      diff, v4, current

    • Added a remark amplifying that the 0-simplex really has no horn, and that one must not think it could be defined to be the empty set (saw long and unresolved MO discussion of this point…)

      diff, v24, current

    • I have added in references to Whitehead’s address ’delivered before the Princeton Meeting of the AM Society on November 2, 1946’ that is ‘combinatorial homotopy 1’.

      diff, v63, current

    • starting page on the type theoretic axiom of choice in contrast to the propositional axiom of choice

      Anonymouse

      v1, current

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

      Anonymous

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • definition, couple of relevant properties, and references

      v1, current

    • In codomain fibration one calls the function

      C \ (-) : C --> Cat

      mapping c to the slice category (C \ c) a pseudofunctor. However I fail to see how this is not functorial.

      A morphism f : a --> b is sent to the functor (C \ f) : (C \ a) --> (C \ b) defined by (g : c --> a) |--> (fg : c --> b), and this assignment clearly satisfies composition. It also preserves identity. So what am I missing here?
    • I added to initial object the theorem characterizing initial objects in terms of cones over the identity functor.

    • for the Café-discussion I added to zero object the details of the proof that in a Set *Set_*-enriched category every terminal or initial object is zero.

      In the course of this I did a bit of brushing-up of a bunch of related entries. For instance at pointed set I made the closed monoidal structure on Set *Set_* manifest, etc.