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    • CommentRowNumber1.
    • CommentAuthorTim_Porter
    • CommentTimeDec 6th 2012

    @Todd. Thanks for correcting my atrocious English!

    Does anyone have any ideas as to how we could provide a bit more for this entry?

    • CommentRowNumber2.
    • CommentAuthorDavidRoberts
    • CommentTimeDec 6th 2012
    • CommentRowNumber3.
    • CommentAuthoradeelkh
    • CommentTimeDec 7th 2012

    I have attempted to incorporate David Roberts' answer from here, along with some other rewriting and reorganization. I should mention that I still haven't actually looked at PS so I hope experts will correct my mistakes.

    • CommentRowNumber4.
    • CommentAuthorTodd_Trimble
    • CommentTimeDec 7th 2012

    Welcome to the nLab and nForum, Adeel!

    Thanks for incorporating the material from David’s response, and thanks for dropping us a line here. If I may just say one thing: I see that you removed some material that had been there. The general custom here these days is to discuss, in case an author edits out material that had been there, why those changes were made (because other authors may wish to defend what they had written). There is no problem retrieving material that was once there, so don’t worry about it, but perhaps we should discuss those changes a little (e.g., if you feel the former version was in some way unfair to Grothendieck).

    • CommentRowNumber5.
    • CommentAuthoradeelkh
    • CommentTimeDec 8th 2012

    Sorry about that, are you referring to this part from the former version?

    Due to the almost free-association style of authorship, there are many back-trackings, corrections and erroneous trains of thought, erroneous in the sense that the author discusses a proposal, and after reflection, corrects his original definition or development. Despite this, the rich ideas lead to a large body of theory, rigorously developed, and to conjectures of considerable weight, some of which have been proved by Denis-Charles Cisinski.

    I felt that the consensus from the MO thread was that this part was unfair to Grothendieck. I think that the description "a sort of research diary of about 600 pages, including many back-trackings and corrections" sufficiently gives a sense of the style without dwelling on it too much. I also wanted to state clearly that PS isn't just ideas and conjectures but also rigorous results.

    • CommentRowNumber6.
    • CommentAuthorTodd_Trimble
    • CommentTimeDec 8th 2012

    No problem! Anyway, I’m not sure about the former version being unfair – but, like you, I haven’t actually looked at Pursuing Stacks. I’d like to hear from others who are more familiar (and were more involved with former versions). Could be that everyone will in the end agree with the present version.

    • CommentRowNumber7.
    • CommentAuthorTim_Porter
    • CommentTimeDec 8th 2012
    • (edited Dec 8th 2012)

    I read PS when it was first produced, as a blog! The style was exactly that of a blog. He comments on the birth of a grandchild, on cooking vegetables in the Korean style, and lots of other things, and there is the record of his false starts, analysis of what goes wrong with the ’obvious’ approach, what he hopes should be true, and occasionally a reasonably solid conjecture. The bulk of the material is very much his working out the basic ideas of the ’modeliser story’. Discussing and comparing various models for homotopy and applying them to his view of what is needed. There is a lot of meat in there (as well as the vegetables).

    In some parts he is reacting to material that Ronnie or myself and others were sending him. For instance, to start with he did not know of Thomason’s ideas on categories as modelling homotopy types. In that case, I gave him the reference and he reacted, I remember, by first being surprised, then commenting on the form of the cofibrations, and finally (and rapidly) incorporating the insights that that had given him into the next few entries in the ’blog’. It is thus a research diary, but much more. He mentions all the scratchwork he was doing before typing the next page of PS.

    As to the edit, I have no objection to this. What was omitted was not that informative, and may be gave the wrong idea. It is a difficult work to describe. I should look out my (slightly incomplete) copy and write some more.

    • CommentRowNumber8.
    • CommentAuthorUrs
    • CommentTimeMar 10th 2014
    • (edited Mar 10th 2014)

    I have updated the links at Pursuing Stacks a lttile, for instance including links to Grothendieck-Maltsiniotis omega-groupoid, to Dimitri Ara’s work on that (beware the hypen bug, which is still in effect-…), also to homotopical alegbraic geometry etc.

    Gave the paragraph on downloadable file versions a section headline, such as not to hide this information in the bulk text.

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeOct 31st 2020

    Gave this entry an actual reference-statement, so that it’s less mysterious which document it’s all about:

    diff, v26, current

    • CommentRowNumber10.
    • CommentAuthorTim_Porter
    • CommentTimeOct 31st 2020
    • (edited Oct 31st 2020)

    Amended from ’goes’ to ’went’ in one place, and fixed a dead link to Ronnie Brown’s web pages.

    diff, v27, current

    • CommentRowNumber11.
    • CommentAuthorTim_Porter
    • CommentTimeOct 31st 2020
    • (edited Oct 31st 2020)

    Duplicate

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