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    • CommentRowNumber1.
    • CommentAuthorjesse
    • CommentTimeMar 8th 2017
    • (edited Mar 8th 2017)

    Created Fraïssé limit.

    (I was pleasantly surprised to see @David_Corfield had posted about the these things a while ago for the n-Category Cafe.)

    Mentioned a neat result of Olivia Caramello’s that omega-categorical structures presentable as Fraisse limits are determined by their automorphism groups GG with the topology of pointwise convergence in a very nice way: their classifying toposes are precisely the toposes of continuous GG-sets.

    To fill in a grey link, I also created an entry for the countable random graph.

    • CommentRowNumber2.
    • CommentAuthorDavid_Corfield
    • CommentTimeMar 8th 2017

    I hope the discussion at the Cafe got things right in the end. I recall plenty of terminological confusion about what kind of limits and embeddings were involved.

    I see my follow-up didn’t generate much discussion.

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