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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeMar 19th 2010

    expanded a bit the discussion of morphisms of sites at site

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeMar 19th 2010
    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJan 16th 2011
    • (edited Jan 16th 2011)

    I have tried to brush-up the entry site a bit.

    • rewrote the former Idea-section

    • gave the definition of morphism of sites in the general form (flat functors instead of left exact, since we don’t demand finite limits in the first place)

    • wrote out most details of the proof that a morphism of sites induces a geometric morphism of sheaf toposes over them

    • reorganized the Examples-section, added a subsection with “classes of examples” and one with “specific examples”.

    There is plenty of room for further improvements.

    • CommentRowNumber4.
    • CommentAuthorzskoda
    • CommentTimeJan 17th 2011
    • (edited Jan 17th 2011)

    flat functors instead of left exact

    It is a matter of how modern we are. Your convention is that you use left exact only in the context of finitely complete categories, but many people use words flat and left exact fully interchangeably. On the other hand, I like that one considers sites which are not necessarily finitely complete.

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeJan 17th 2011

    Okay, in any case, the previous version of the entry said “finite-limit preserving functor”.

    • CommentRowNumber6.
    • CommentAuthorUrs
    • CommentTimeApr 27th 2011

    added to site more statements about the relation between morphisms of sites and geometric morphisms of their sheaf toposes

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeApr 27th 2011

    I thought of what I think is a good (or at least better than before) statement about the Idea of a site

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeApr 27th 2011

    I have added one more theorem and two more detailed proofs to site.

    • CommentRowNumber9.
    • CommentAuthorTim_Porter
    • CommentTimeFeb 28th 2013

    At site there is a strange ’reference’ (\ref{LemmaForClassifyingToposes}) that looks as if it is left over from a cut-and-paste from a latex document. Does anyone know to what it ’refers’?

    • CommentRowNumber10.
    • CommentAuthorUrs
    • CommentTimeFeb 28th 2013
    • (edited Feb 28th 2013)

    I suppose what is meant is this corollary at classifying topos.

    I have fixed the links.

    • CommentRowNumber11.
    • CommentAuthorTim_Porter
    • CommentTimeFeb 28th 2013

    Thanks. (I’ve just fixed a spelling typo there.)

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