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

Discussion Tag Cloud

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).
    • CommentRowNumber1.
    • CommentAuthorJan Pax
    • CommentTimeOct 5th 2014
    • (edited Oct 5th 2014)

    Let U,VU,V be functors between categories CC and XX.
    Why a dinatural transformation {*}hom X(U,V)\{*\}\xrightarrow{\cdot \cdot}\hom_X(U-,V-) is a function which selects a natural transformation UVU\xrightarrow{\cdot} V ?

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeOct 9th 2014

    Essentially by definition.

    Are you asking for somebody to unwind the definition a bit more?

    • CommentRowNumber3.
    • CommentAuthorFosco
    • CommentTimeOct 10th 2014

    Urs, the OP asked similar questions on math.SE, which I promptly (and hopefully properly) answered. The main problem was that he (she?) misunderstood the meaning of the construction proposed by Mac Lane. I hope now all has been clarified.

    If not, dear Jan Pax, feel free to contact me! (just comment on the thread on math.SE)

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeOct 11th 2014

    Okay, thanks!

    If there is any explanation that would usefully be added to the nLab entry dinatural transformation, please consider doing so.