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    • CommentRowNumber1.
    • CommentAuthorYuxi Liu
    • CommentTimeJul 2nd 2020

    more examples

    diff, v20, current

    • CommentRowNumber2.
    • CommentAuthorYuxi Liu
    • CommentTimeJul 2nd 2020

    more Reedy category example, and the proof that all isomorphisms in a Reedy category are identities.

    diff, v21, current

    • CommentRowNumber3.
    • CommentAuthorMike Shulman
    • CommentTimeJan 28th 2021

    I removed this paragraph from immediately following the definition:

    That is, we have two subcategories R +R_+ and R R_-, such that all arrows in R +R_+ are degree-raising (more precisely, non-degree-lowering) and all arrows in R R_- are degree-lowering, and every arrow in RR is uniquely decomposible as a degree-lowering followed by a degree-raising.

    I don’t see that it adds anything; it just restates the definition in a less-precise and potentially confusing way. (And I just had an email conversation with someone who was actually confused by it.)

    diff, v24, current