Not signed in (Sign In)

Not signed in

Want to take part in these discussions? Sign in if you have an account, or apply for one below

  • Sign in using OpenID

Site Tag Cloud

2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry book bundles calculus categorical categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex complex-geometry computable-mathematics computer-science constructive cosmology deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration foundation foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck group group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory homological homological-algebra homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory k-theory lie-theory limit limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monad monads monoidal monoidal-category-theory morphism motives motivic-cohomology nlab noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pages pasting philosophy physics pro-object probability probability-theory quantization quantum quantum-field quantum-field-theory quantum-mechanics quantum-physics quantum-theory question representation representation-theory riemannian-geometry scheme schemes set set-theory sheaf simplicial space spin-geometry stable-homotopy-theory stack string string-theory subobject superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory tqft type type-theory universal variational-calculus

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

Welcome to nForum
If you want to take part in these discussions either sign in now (if you have an account), apply for one now (if you don't).
  1. removing “category: category theory” as we don’t want cycles in the categories. also a category with only one page is not worth much and a category called “category theory” is a pleonasm

    Valeria de Paiva

    diff, v2, current

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeNov 7th 2020
    • (edited Nov 7th 2020)

    As far as I am concerned, you may indeed feel free to remove these category labels. As I mentioned before and as you notice here, they have never been in wide-spread systematic use anyways (while instead the floating context menus have been).

    Just to notice that the reasons you give here for removing the label don’t seem to be sensible to me:

    1. There is no “cycle” here, is there?

    2. If there is really only one entry with category “category theory” and if you care about the category-system, then the conclusion would be to add that label to all other entries on category theory.

    3. There is no pleonasm here. (Or maybe you are joking?)

    I appreciate if you and others feel energetic about cleaning up this bit of the nLab. Let’s just make sure we all understand what’s going on:

    A few users have experimented, in the past, with using Instiki’s category-functionality for organizing entries into topic clusters. Since, however, this functionality just provides users with a blindly ordered list of links (which, when long, is hard to read and hence hard to take hints from) others have instead used floating context menus of related entries (which may be formatted nicely such as to be more helpful to the reader – on Wikipedia they have similar boxes for collecting pointers to related entries). As far as I am aware, the latter has found wide-spread systematic use, mainly because that’s the system that I have adopted.

    Of course both systems can exist in parallel.

    Anyone energetic about cleaning up the nLab who thinks the category-labels are more or as useful than the floating context menus should add loads of them. Every single entry on category theory should have a label category: category theory, so that they are actually all grouped and linked together this way.

    Anyone energetic about cleaning up the nLab who thinks the category-labels are less useful and potentially misleading as long as they are incomplete should go and remove them all, and instead replace them with usefully organized and nicely formatted floating context menus.

    The best solution would be if somebody with some coding skill could look into this. If a category-label in the source would automatically trigger the appearance of a nicely formatted floating context menu, that would finally be the solution that combines the idea of automated context (which must have driven the Instiki programmers who introduced that category-functionality) while improving it to the degree that it becomes actually useful on a larger Wiki (which the Instiki developers don’t seem to have anticipated).

    • CommentRowNumber3.
    • CommentAuthorvarkor
    • CommentTimeMar 9th 2023

    Added cross-reference to pullback.

    diff, v3, current

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeMar 9th 2023

    tried to brush-up wording, formatting and hyperlinking of this poor entry

    diff, v4, current

    • CommentRowNumber5.
    • CommentAuthorvarkor
    • CommentTimeMar 14th 2023

    Mention relationship to double functors.

    diff, v5, current