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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeOct 31st 2013

    added to orbit category a remark on what the name refers to (since I saw sonebody wondering about that)

    • CommentRowNumber2.
    • CommentAuthorDavid_Corfield
    • CommentTimeOct 31st 2013

    Since Mackey functor is only a stub, I added a ’Guide’ in the references

    • CommentRowNumber3.
    • CommentAuthorDavidRoberts
    • CommentTimeNov 1st 2013

    Some small changes at orbit category (including making OrG\mathrm{Or}\, G into OrG\operatorname{Or}G throughout).

    • CommentRowNumber4.
    • CommentAuthorTodd_Trimble
    • CommentTimeNov 1st 2013
    • (edited Nov 1st 2013)

    The difference between the results of \mathrm{}\backslash, and \operatorname{} is invisible to my eyes.

    • CommentRowNumber5.
    • CommentAuthorDavidRoberts
    • CommentTimeNov 1st 2013
    • (edited Nov 4th 2013)

    The space induced by the backslash-comma combination looked too big to me. But never mind.

    • CommentRowNumber6.
    • CommentAuthoradeelkh
    • CommentTimeNov 4th 2013
    • (edited Nov 4th 2013)

    There is also another construction which goes by the name of “orbit category”: when T:𝒜𝒜T : \mathcal{A} \to \mathcal{A} is an additive automorphism, the orbit category 𝒜/T\mathcal{A}/T is the one with the same objects as 𝒜\mathcal{A}, and in which morphisms are given by 𝒜/T(X,Y)= iZ𝒜(X,T i(Y))\mathcal{A}/T(X, Y) = \bigoplus_{i \in \mathbf{Z}} \mathcal{A}(X, T^i(Y)). This has appeared under the name “orbit category” in papers of Keller, Tabuada, and others. Perhaps we should mention this somewhere on the page?

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeNov 4th 2013

    If you have time, please do!

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeOct 24th 2020
    • (edited Oct 24th 2020)

    added graphics showing the orbit categories of the first five cyclic groups (here)

    diff, v25, current

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