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    • 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.

    • brief category:people-entry for hyperlinking edit log signatures

      v1, current

    • Wrote a bunch of stuff on determinant. Just because I felt like it. But I’ve run out of steam to do more on it now.

    • renamed from “Steenrod-Wockel approximation theorem” to “Steenrod approximation theorem”

      diff, v13, current

    • starting page to make links work

      Anonymouse

      v1, current

    • Adding reference

      as a construction of the locale of real numbers can be found in section 5.3 of that article

      Anonymous

      diff, v20, current

    • Added to one-sided real number a short discussion of the correspondence of internal lower reals in a sheaf topos Sh(X)\mathrm{Sh}(X) and upper semicontinuous functions X{+}X \to \mathbb{R} \cup \{ +\infty \}.

    • Created categorical model of dependent types, describing the various different ways to strictify category theory to match type theory and their interrelatedness. I wasn’t sure what to name this page — or even whether it should be part of some other page — but I like having all these closely related structures described in the same place.

    • Test edit, I can’t seem to get the page to accept the larger edit I’ve made.

      diff, v26, current

    • Added a remark that the Elephant briefly refers to gaunt categories as “stiff”.

      diff, v4, current

    • added some references, formatting and cross-links. Also touched the wording.

      diff, v4, current

    • Happening upon this old entry, I have adjusted the wording of the very first paragraph.

      (There is more room left to streamline this entry…)

      diff, v9, current

    • finding that an entry like this has been missing all along (all we seem to have had was this paragraph at enriched category) I have now created it with some minimum content, for completeness

      v1, current

    • Added doi and pointer to relevant sections to

      • Marcelo Aguilar, Samuel Gitler, Carlos Prieto, section 6 of Algebraic topology from a homotopical viewpoint, Springer (2002) (toc pdf, doi:10.1007/b97586)

        (EM-spaces are constructed in section 6, the cohomology theory they represent is discussed in section 7.1, and its equivalence to singular cohomology is Corollary 12.1.20)

      diff, v25, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • brief category:people-entry for hyperlinking references

      v1, current

    • stub for 2-topos (mostly so that the links we have to it do point somewhere at least a little bit useful)

    • I’ve removed this query box from metric space and incorporated its information into the text:

      Mike: Perhaps it would be more accurate to say that the symmetry axiom gives us enriched \dagger-categories?

      Toby: Yeah, that could work. I was thinking of arguing that it makes sense to enrich groupoids in any monoidal poset, cartesian or otherwise, since we can write down the operations and all equations are trivial in a poset. But maybe it makes more sense to call those enriched \dagger-categories.

    • Created page, added basic content.

      v1, current

    • Created page. Adding more as we speak.

      v1, current

    • For now creating page, it needs to be (much) further expanded.

      v1, current