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    • CommentRowNumber1.
    • CommentAuthorMike Shulman
    • CommentTimeMar 10th 2010
    • (edited Mar 10th 2010)

    Added some remarks, mostly about extensivity and exactness, to quasitopos.

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeOct 20th 2010

    added a bunch of propositions to quasitopos

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeOct 26th 2010

    added references to quasitopos and concrete sheaf

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeDec 8th 2011

    added a pointer to Garner and Lack which appeared earlier this year.

    • CommentRowNumber5.
    • CommentAuthorTodd_Trimble
    • CommentTimeOct 3rd 2013

    Some slight rearrangement of examples, recognizing five of them as examples of ¬¬\neg\neg-separated presheaves. See this MSE thread.

    • CommentRowNumber6.
    • CommentAuthorMike Shulman
    • CommentTimeMar 1st 2018

    We discovered on MO that the page quasitopos has contained an incorrect definition of “Grothendieck quasitopos” for the past 8 years, which was apparently my fault originally. Ugh. Now fixed.

    • CommentRowNumber7.
    • CommentAuthorTodd_Trimble
    • CommentTimeMar 1st 2018

    I added a second characterization for Grothendieck quasitopos.

    • CommentRowNumber8.
    • CommentAuthorpcapriotti
    • CommentTimeSep 25th 2018

    Added a little bit more information to the remark about the alternative definition of quasitopos, and a reference to Wyler for the trickiest step in the proof.

    diff, v29, current

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